Bio-based polyelectrolyte complex compositions with increased hydrophobicity comprising fatty compounds
11685820 · 2023-06-27
Assignee
Inventors
Cpc classification
C08L1/286
CHEMISTRY; METALLURGY
B05D1/00
PERFORMING OPERATIONS; TRANSPORTING
D06N3/0059
TEXTILES; PAPER
C08L5/08
CHEMISTRY; METALLURGY
C08L5/08
CHEMISTRY; METALLURGY
D06B1/00
TEXTILES; PAPER
C08L1/286
CHEMISTRY; METALLURGY
B05D5/08
PERFORMING OPERATIONS; TRANSPORTING
International classification
C08L5/08
CHEMISTRY; METALLURGY
B05D1/00
PERFORMING OPERATIONS; TRANSPORTING
B05D5/08
PERFORMING OPERATIONS; TRANSPORTING
D06B1/00
TEXTILES; PAPER
Abstract
The invention relates to a bio-based polyelectrolyte complex (PEC) composition suitable as a binder for fiber based materials, textiles, woven and nonwoven materials, said PEC composition comprising cationic biopolymer, anionic biopolymer, acid and a preservative, and wherein the net charge of the PEC is cationic, the charge ratio of the anionic polymer and the cationic polymer is ≤1, the cationic biopolymer is chitosan, the anionic biopolymer is a polyanion derived from nature, the acid is a Brønsted acid and/or a Lewis acid, wherein the Brønsted acid is selected from any organic and/or inorganic acids, and wherein the Lewis acid is selected from any cationic mono- or multivalent atom, the weight ratio between cation and anion is 1:0.1 to 1:20, the weight ratio between the cation and acid is 1:0.01 to 1:30, chitosan has a degree of deacetylation being 66-100%, the pH is less than 7, and wherein said composition further comprises one or more fatty compounds as well as methods and use thereof. The present invention further relates to a method for preparing the PEC composition, uses of the PEC composition, as well as method of treating materials with the PEC composition.
Claims
1. A method of treating materials selected from fiber based materials, textiles, woven and nonwoven materials the method comprising: a) applying to said materials an emulsion or dispersion binder composition comprising a biobased polyelectrolyte complex (PEC) composition suitable as a binder, wherein said PEC composition comprises a cationic biopolymer, an anionic biopolymer, an acid, a preservative and one or more fatty compounds, wherein, the net charge of the PEC composition is cationic, the charge ratio of the anionic biopolymer and the cationic biopolymer is ≤1, the cationic biopolymer is chitosan, wherein chitosan has a degree of deacetylation being 66-100%, the anionic biopolymer is a polyanion derived from nature, the acid is a Brønsted acid and/or a Lewis acid, wherein the Brønsted acid is selected from any organic and/or inorganic acids, wherein the Lewis acid is selected from any cationic mono- or multivalent atom, the weight ratio between cationic biopolymer and anionic biopolymer is 1:0.1 to 1:20, the weight ratio between the cationic biopolymer and acid is 1:0.01 to 1:30, the pH is less than 7, the one or more fatty compounds comprises one or more of sunflower oil, soy bean oil, tall oil, corn oil, rapeseed oil, coconut oil and palm oil and wherein the weight ratio of PEC:fatty compound in said PEC composition is from 1:0.5 to 1:1; and b) obtaining both an increase in a hydrophobicity of the materials and an increase in at least one mechanical property of the materials selected from dry strength, wet strength, tensile stiffness and tensile softness.
2. The method of treating materials according to claim 1, wherein said fiber based material consists of paper and/or paperboard and said treatment is performed either during manufacture of said paper and/or paperboard or on already finished paper and/or paperboard.
3. The method of treating materials according to claim 1, comprising the steps of; a. treating the fiber based materials, textiles, woven and nonwoven materials with the PEC composition by one or more of: i. adding to suspensions of fiber based materials, textiles, woven and nonwoven materials, ii. spray coating, iii. dip coating, iv. roll coating, v. impregnation, vi. padding, vii. screen coating, viii. printing, ix. direct coating methods including knife coating, blade coating, wire wound bar coating, round bar coating and crushed foam coating, x. indirect coating methods including mayer rod coating, direct roll coating, kiss coating, gravure coating and reverse roll coating, and xi. ink jet and/or slit-die/slot-die; and b. optionally curing the treated fiber based materials, textiles woven and nonwoven materials, preferably the curing is performed at 20° C. to 200° C.
4. The method according to claim 3, comprising curing the treated fiber based materials, textiles, woven and nonwoven materials, preferably the curing is performed at 120° C. to 180° C.
5. The method according to claim 1, comprising diluting the PEC composition with water selected from distilled water, tap water, and deionized water prior to the step of applying to said materials the emulsion or dispersion binder composition comprising the PEC composition.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
(4) The present invention relates to bio-based PEC compositions that are environmentally benign, renewable and biodegradable mixtures of a cationic biopolymer and an anionic biopolymer. The cationic and anionic polymers are balanced so that the net charge of the PEC is cationic. The PEC compositions are prepared in the presence of an acid and preservative and further comprise one or more fatty compounds. The PEC compositions are suitable as binders for fiber based materials, textiles, woven and nonwoven materials, as well as hydrophobic surface treatment of said materials or as additives in wet end paper making.
(5) According to the invention the use of the wording textiles, woven and nonwoven may include cloths or fabrics and may be based on natural or synthetic fibers and mixtures thereof. Textiles, woven and nonwoven may consist of a network of natural and/or synthetic fibers often referred to as thread or yarn. Yarn is produced by spinning raw fibers of wool, flax, cotton, or other material to produce long strands. Textiles are formed by weaving, knitting, crocheting, knotting, or pressing fibers together (felt). The words fabric and cloth may for example be used in textile assembly trades (such as tailoring and dressmaking) as synonyms for textile. Textile may refer to any material made of interlacing fibers or nonwoven textiles. Fabric refers to any material made through weaving, knitting, spreading, crocheting, or bonding that may be used in the production of further goods (garments, etc.). Cloth may be used synonymously with fabric but often refers to a finished piece of fabric used for a specific purpose (e.g., table cloth). The wording textiles, woven and nonwoven according to the present invention may include all different types of textiles described above. Textiles, woven and nonwoven according to the invention can be made from many different types of materials and fibers for example animal, plant, wood, mineral, synthetic, sugar based, protein based for example wool, silk, mohair, cashmere, pygora, cameldown, alpaca, ilama, vicuna, guanaco, angora, qiviut, ramie, nettle, milkweed, cotton, linen, flax, jute, hemp, viscose, asbestos, glass fiber, rock fiber, nylon, elastan, polyester, acrylic, polyamide, polypropylene, polyurethane and its derivatives, cornfiber, coir, yucca, sisal, bamboo (rayon) fiber, peanut, soybased, chitin based, milk casein based, keratin based and poly lactic acid based etc. Further, nonwoven materials are fabric-like materials made from long fibers, bonded together by chemical, mechanical, heat or solvent treatment. Nonwoven fabrics are also defined as sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically. The term is used in the textile manufacturing industry to denote fabrics, such as felt, which are neither woven nor knitted. They are flat or tufted porous sheets that are made directly from separate fibers, molten plastic or plastic film.
(6) Fiber based materials refer to materials such as paper materials which comprise a high degree of cellulose. As will be understood by those skilled in the present field of art, numerous changes and modifications may be made to the above described and other embodiments of the present invention, without departing from its scope as defined in the appending claims. For example, the pulps for making fiber based materials may be any kind of pulp, i.e. mechanical pulp, thermo-mechanical pulp, chemo-mechanical pulp, sulphate pulp, sulphite pulp, bleached pulp, unbleached pulp, short-fiber pulp, long-fiber pulp, recycled fibers, mixtures of different pulp grades etc. The invention works irrespective of the kind of pulp chosen.
(7) The Examples relate to comparative studies for investigating the emulsifying and dispersion properties of the PEC compositions comprising different fat and oils compounds. Besides creating a good emulsion and/or dispersion, it is the object of these studies, to investigate the possibility to transfer the properties of the emulsified and/or dispersed compounds from the PEC composition to different materials.
(8) The PEC composition of the present invention can be used as a vehicle in the sense that the composition both has space for and fuel to transport other molecules. In more specific terms, the PEC composition can form a micelle around for example fatty compounds contained in the PEC composition and thanks to its positive charge, it can thereafter arrange itself towards negatively charged fibers and thus transfer the properties of the fatty compounds to the fiber material.
EXPERIMENTAL SECTION
(9) Charge Ratio
(10) Charge density was measured using the Mütek PCD 02 device. Charge (symbol: q, unit: meqv) was calculated using Eq. 1.
q[meqv]=C.sub.counter ion [eqv/1].Math.V.sub.counter ion [1].Math.1000 (1)
where the counter ion is one of sodium polyethylenesulphate (PES-Na, anionic) or poly-diallyl-dimethyl-ammonium-chloride (poly-dadmac, cationic), depending on the charge of the colloid. If the charge at different concentrations are plotted against mass of the current colloid, the charge density (unit: meqv/g) is the slope of the linear curve. The mass of the colloid can be calculated with Eq. 2.
m [g colloid]=wt % colloid [g colloid/g solution].Math.g [g solution for 10 ml].Math.0,0 (2) When the charge densities were known for one polycation and one polyanion, the charge ratio was calculated between the polyelectrolytes so that the overall charge of the complex became positive (i.e. charge ratio <1), see Eq. 3.
(11)
(12) The method above is for measuring charge density and then calculate the charge ratio.
(13) Experiments 1-12—Study of Various Fatty Compounds included in the PEC Composition and Evaluation of Said PEC Compositions on Nonwoven and Textiles
(14) A majority of the 100% bio based binders on the market are hydrophilic. To increase the market share for bio based binders, hydrophobicity must be included within the binder characteristics together with mechanical properties such as stiffness and/or softness and dry- and wet strength. The binder recipe OC-C (see details in abbreviations experiments 1-12) is based on polyelectrolyte complex (PEC). PEC gives good dry and wet mechanical properties to fiber based materials, nonwovens, paper and textiles. PEC can also be seen as a micelle that can emulsify for example fatty compounds. To mix PEC and fatty compounds can therefore lead to an emulsion/dispersion that both gives good mechanical properties to materials (the PEC part of the emulsion) and that creates a hydrophobic surface on the material (the fatty part of the emulsion).
(15) The experiments below demonstrate that PEC can support and stabilize fatty compounds in water to form emulsions/dispersions. These are then further used as binders/additives on different materials and the properties measured. In the following examples the term fatty PEC composition refers to polyelectrolyte complex emulsion/dispersion containing a fatty compound while a polyelectrolyte complex formulation without fatty compounds is called non-fatty PEC composition
(16) Equipment used in Experiments 1-12
(17) List of equipment used in experiments 1-12. pH in formulations was measured with pHenomenal pH1000H from VWR with Hamilton Polilyte Lab Temp BNC electrode (calibrated with buffers pH 4, 7 and 10). Tensile tests were conducted using Testometric M250-2.5AT (machine capacity 2.5 kN) together with Wintest Analysis software. Homogenization of formulations in lab scale was done using IKA T25 digital Ultra-Turrax. Viscosity of formulations were measured with Brookfield DV-II+ Pro LV Viscometer together with Rheocal software using spindle LV4 at 200, 150, 100, 50, 10 and 6 rpm. Coating of paper and nonwoven was performed with Wichelhaus WI-MU 505 A horizontal padder. Drying of treated paper and nonwoven was done in an oven from Termaks (with stenter frame from Wichelhaus Wi-LD3642 Stenter). Drying of material pieces after wash was performed in a Termaks oven, suspended by clamps. Washing was done in standardized machine Electrolux Wascator FOM71 CLS. Visual evaluation of emulsions was conducted usinga Nikon Microphot—FXA with 10× lens.
(18) Chemicals used in Experiments 1-12
(19) Below, all chemicals used in experiments 1-12 are listed.
(20) TABLE-US-00001 Producer/ Chemical name Commercial name Distributor 1,2-Benzisothiazol-3(2H)-one, Nipacide BSM Clariant 2-methyl-2H-isothiazol-3-one Carboxymethyl cellulose FinnFix 5 CP Kelco Castor oil Cargill Chitosan Chitosan 90/ Kraeber 100/A1 Chitosan Chitosan Zheijiang Aoxin Biotechnology Citric acid monohydrate Citronsyra Mono Univar AB E33 8-80M LT Epoxidized soy bean oil Soyflex 6330 Soyventis/ Vendico Hydrogenated methyl ester of Hercolyn D Pinova rosin Isosorbid ester Polysorb ID 46 Roquette Lecithin Lechiprime Cargill 1000 IP Methyl ester of rosin Abalyn Pinova Octanoic acid Acros organics Oleic acid Alfa aeser Polyol ester Oxi-cure 2000 Cargill Potassium cocoate Eurasol KPZ EOC/IMCD Potassium palmate Eurasol PZT EOC/IMCD Potassium tallate Eurasol KT EOC/IMCD Rapeseed oil ICA Sorbitan laurate Span 20 Croda Sorbitan oleate Span 80 Croda Sorbitol Neosorb 70 Roquette Soy bean stand oil SEH 77 7P Oleon/Vendico Soy bean stand oil SEH 77 30P Oleon/Vendico Sunflower oil ICA Sunflower oil Sunflower oil AAK 745100 Sunflower oil Cargill Sunflower oil, high oleic High oleic Cargill sunflower oil Tall oil fatty acid Sylfat 2 Arizona/IMCD
(21) Abbreviations in Experiments 1-12
(22) Below, all abbreviations used in experiments 1-12 are listed.
(23) TABLE-US-00002 C Chitosan CMC Carboxymethyl cellulose CO Castor oil ESBO Epoxidized soy bean oil, Soyflex 6330 NW Nonwoven OA Octanoic acid OC-A (2 wt % chitosan 90/100/A1, 12 wt % citric acid mono hydrate, 0.2% Nipacide BSM, the rest is water) produced by dispersing chitosan in 73.8 wt % water and citric acid mono hydrate in 12 wt % water and pour the citric acid solution to the chitosan dispersion during homogenization. Homogenize for 10 min and add then the biocide. Homogenize 1 min more. OC-B (0.75 wt % chitosan, 0.75 wt % Finnfix 5, 9 wt % citric acid mono hydrate, 25 wt % Neosorb 70, 0.2 wt % Nipacide BSM) Produced with method 14 OC-C (2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 0.2 wt % Nipacide BSM, the rest is water) Produced with method 12 OC-D (2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 2 wt % sunflower oil from ICA, 0.2 wt % Nipacide BSM, the rest is water) Produced with Method 13 OC-E (2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 2 wt % sunflower oil 745100 (from AAK), 0.2 wt % Nipacide BSM, the rest is water) Produced with Method 13 OC-F (2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 2 wt % sunflower oil (from Cargill), 0.2 wt % Nipacide BSM, the rest is water) Produced with Method 13 OC-G (2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 2 wt % high oleic sunflower oil (from Cargill), 0.2 wt % Nipacide BSM, the rest is water) Produced with Method 13 PEC Polyelectrolyte complex RH Relative humidity RO Rapeseed oil RT Room temperature S2 Tall oil fatty acid, Sylfat 2 SO Sunflower oil PES Polyester PLA Polylactic acid
(24) Methods Employed in Experiments 1-12
(25) Below, all methods employed in experiments 1-12 are listed. Method 1: 50 g formulation is homogenised with Ultra Turrax T25 with speed 9000 rpm during 1 minute after the addition of oil. Method 2: Coating of nonwoven and fabric with padder with speed 11.6 and pressure 0.1 MPas. Drying in Termaks oven in a stenter frame in 150° C. for 3 minutes. Method 3: Pictures taken through the ocular with the camera of the mobile phone LG G3. Lens in the microscope is 10×. Method 4: A wash cycle with five washes in 40° C. standard program (Procedure No. 4N from ISO/CD 6330) with standard detergent (IEC(A)—2012: n. 6—containing optical brightener—pink label—detergent n. 3 in the standard) followed by drying in Termaks oven in 150° C. in 3 min between the washes was performed. Method 5: Test of hydrophobicity by putting drops of water on the surface. Grades for hydrophobicity: −−=hydrophilic and spreading, −=hydrophilic, +=droplet stays around 1 s, ++=droplet stays 10-30 s, +++=droplet stays >60 s and is defined as hydrophobic. Method 6: Formulations diluted to 1 wt % (based on dry content measured with Method 9) and nonwoven treated with padder with speed 11.6 and pressure 0.1 MPa followed by drying in stenter frame in Termaks oven 150° C. for 3 min, suspended with clothespins. Method 7: Tensile test for dry nonwoven were performed by using Testometric M250-2.5AT (pretension: 0.01 N, sample length: 200 mm, width: 50 mm, speed: 100 mm/min, Load cell 1: 50 kgf) after having test specimens at least 20 h in 23° C. and 50% RH. Three nonwoven sheets were treated and two test specimen for each treated piece was cut out and tested. Method 8: Tensile test for wet nonwoven were performed by using Testometric M250-2.5AT (pretension: 0.01 N, sample length: 200 mm, width: 50 mm, speed: 100 mm/min, Load cell 1: 50 kgf) after having test specimens at least 20 h in 23° C. and 50% RH and then soaked in water for 15 min. Three nonwoven sheets were treated and two test specimen for each treated piece was cut out and tested. Method 9: Dry content was measured by putting three times 10 g of the formulation in aluminium cups in the Termaks oven for 20-24 h (105° C.). The theoretical dry content was then calculated by the equation (W2−W0)/W1 where W0=weight of the cup, W1=weight of the original sample, W2=weight of the cup and the final sample. Method 10: Formulations diluted to 1 wt % and nonwoven treated with padder with speed 11.6 and pressure 0.1 MPa followed by drying in stenter frame in stenter frame oven for different elevated temperatures and times. Method 11: General description of production method for non-fatty PEC composition without oil/fat as additive (100 g formulation): 1. Homogenize 71.8 g water and 2 g CMC Finnfix 5 with Ultraturrax T25 at 9000 rpm for 3 min. 2. Disperse 2 g chitosan in the CMC-solution. 3. Dissolve 12 g citric acid mono hydrate in 12 g water and add to the biopolymer solution. Homogenize at 12000 rpm for 3 min. 4. Add 0.2 g Nipacide BSM. Homogenize 1 min. Method 12: General description of production method for fatty PEC composition (100 g formulation): 1. Homogenize 69.8 g water and 2 g CMC Finnfix 5 with Ultraturrax T25 at 9000 rpm for 5 min. 2. Disperse 2 g chitosan in the biopolymer solution. 3. Dissolve 12 g citric acid mono hydrate in 12 g water and add to the CMC-solution. Homogenize at 12000 rpm for 5 min. 4. Add 2 g oil/fat to the mixture. Homogenize at 12000 rpm for 5 min. 5. Add 0.2 g Nipacide BMS. Homogenize 1 min. Method 13: General description of production method for fatty PEC composition comprising a water soluble plasticizer (100 g formulation): 1. Homogenize 40 g water and 25 g Neosorb 70 for 2 min. 2. Add 0.75 g CMC Finnfix 5 and homogenize with Ultraturrax T25 at 9000 rpm for 5 min. 2. Disperse 0.75 g chitosan in the CMC-solution. 3. Dissolve 9 g citric acid mono hydrate in 24.3 g water and add to the biopolymer solution. Homogenize at 9000 rpm for 5 min. 4. Add 0.2 g Nipacide BSM. Homogenize 1 min.
(26) Experiment 1—Study of the Emulsifying Properties of PEC
(27) In experiment 1, oil or fatty acid was added to water solutions of CMC, chitosan or PEC respectively, to investigate the emulsifying properties of the different biopolymers. The ratio between PEC or polymer to oil are described in Table 1. The emulsions were prepared according to Method 1.
(28) TABLE-US-00003 TABLE 1 Recipes for fatty PEC compositions Polymers and PEC used as Ratio polymer emulsifier or PEC to for the oil Oil or fatty or fatty acid Fatty acid compound Stability at 23° C. OC-A Octanoic acid C:OA 1:0.1 Creaming < 1 day C:OA 1:1 Creaming < 1 day Sunflower oil.sup.1) C:SO 1:0.1 Creaming < 1 day C:SO 1:1 Creaming < 1 day OC-C Octanoic acid PEC:OA 1:0.1 Creaming < 1 day PEC:OA 1:0.5 Creaming < 1 day Sunflower oil.sup.1) PEC:SO 1:0.05 No Creaming within 7 day PE:SO 1:0.5 No Creaming within 7 day PEC:SO 1:1 Creaming within 5 day PEC:SO 1:2 Creaming within 5 day 10 wt % Sunflower oil CMC:SO 1:1 No emulsion FinnFix 5 formed .sup.1)From ICA
(29) Stable emulsions were obtained from PEC:SO 1:0.05 and PEC:SO 1:0.5. Microscopic evaluation of the PEC:SO 1:0.5 emulsion according to Method 3 shows an even particle size distribution containing small spherical emulsion droplets.
(30) The emulsion of PEC:SO 1:0.5 was also tested by diluting it with water to see if sedimentation/precipitation/creaming/floating/phase inversion happened. The emulsion did not show any signs of separation within 7 days.
(31) Experiment 2—Study of the Hydrophobicity Imparted by Fatty PEC Composition
(32) Coating method 2 was used for applying fatty PEC compositions in table 1 on 100% viscose nonwoven material. The hydrophobicity was tested by putting droplets of water on the treated material. For OA with both C and PEC, the material was hydrophilic. For the ratios 1:0.1 of C:SO and PEC:SO the material was hydrophilic. For ratio PE:SO 1:0.5, 1:1 and 1:2 and C:SO 1:1 the materials got a hydrophobic character which further improved at after 5 days of treatment. Water droplets added to the mature hydrophobic material stayed on the surface until evaporated and were not absorbed.
(33) CMC followed the same trend as C and PEC regarding development of the hydrophobicity over time. However, one week after treatment the droplets stayed on the surface for one minute but was thereafter absorbed by the material.
(34) Experiment 3—Study of the Hydrophobicity Imparted by fatty PEC Composition through Contact Angle Measurements
(35) Static contact angle was measured on the 100% viscose nonwoven treated with PEC:SO 1:0.5. Formulation was produced according to Method 1 and the material was treated according to Method 2. The contact angle measurement was performed six days after treatment showing the following contact angles: 129.5°, 126.7°, 120.7°, 122.9°, 127.3° 118.0° and 124.3° yielding an average contact angle of 124.2°. Dynamic contact angle for the same material over a period of 60 s s is seen in Table 2.
(36) TABLE-US-00004 TABLE 2 Dynamic contact angle for 100% viscose NW with PEC:SO 1:0.5 treated six days before the test. Contact angle [°] Test 1 s 30 s 60 s 1 129.0° 128.3° 127.2° 2 125.4° 125.4° 127.2° 3 125.9° 125.4° 126.2°
(37) No contact angle could be measured on same nonwoven material treated with non-fatty PEC composition.
(38) Experiment 4—Study of the Stability of the fatty PEC Compositions at 40° C. and 50° C.
(39) OC-D produced according to Method 12 was stored at 40° C. and 50° C. A thin line of creaming was observed on the surface, however but the creaming was easily redispersed when stirred.
(40) NW treated with OC-D that had been stored one month at 50° C. and one and a half month at 40° C. show the same hydrophobicity as freshly produced OC-D. NW was treated according to Method 2 and the hydrophobicity was evaluated according to Method 6 (see Table 3).
(41) TABLE-US-00005 TABLE 3 Hydrophobicity for NW treated with aged formulations. Time and elevated temperature that Day 2 after Day 5 after OC-D was exposed to treatment treatment 30 days in 50° C. ++ to +++ .sup.1) +++.sup.3) 45 days in 40° C. +++ .sup.2) +++.sup.3) Freshly produced OC-D ++ to +++ .sup.1) +++.sup.3) .sup.1) All drops gone after 60-70 s. .sup.2) Half the amount of drops are still on the surface after five minutes. .sup.3)All drops are still on the material after ten minutes and they are easily rolled off when the material is tilted.
(42) No difference can be observed between the differently fresh and aged fatty PEC compositions of the invention.
(43) Experiment 5—Study of the Washing Durability of the Hydrophobicity on NW Material Treated with PEC Composition
(44) To investigate if the oil in the PEC composition is covalently bounded the material it was tested to wash a piece of 100% viscose NW according to Method 4. The wash was performed 3 weeks after treatment with the PEC composition OC-D. The hydrophobicity was not affected by the washing.
(45) Experiment 6—Hydrophobizing Performance and Durability of Fatty PEC Composition on Different Materials
(46) To investigate if fatty PEC composition OC-D transfers hydrophobicity to different types of fibres, and not only viscose as tested above, a test was performed applying OC-D according to Method 2 on the following textiles and NWs 1. 100% hemp plain weave, 203 g/m.sup.2, textile 2. 100% cotton sateen, white, 145 g/m2textile 3. Printed cotton, different colors, textile 100% polyester, white, textile 4. 100% PLA, white, textile 5. 100% polyester, white, nonwoven,
(47) The pieces were treated with diluted OC-D, either 1 part OC-D+1 part water (called 1:1) or 1 part OC-D and 4 parts water (called 1:4) and coated according to Method 2. See hydrophobicity results (before and after washing according to Method 4) in Table 4 and hydrophobicity vs stiffness in
(48) TABLE-US-00006 TABLE 4 Hydrophobicity on materials treated with 1:1 or 1:4 dilutions of OC-D after washing according to Method 4. The hydrophobicity was evaluated according to Method 5. Material and the dilution (OC-D: water) used Before wash After 1 wash Cotton textile, + sateen, reference Cotton textile, ++ +++ sateen, 1:4 Cotton textile, − +++ sateen 1:1 Cotton textile, − printed, reference Cotton textile, − ++ printed 1:4 Cotton textile, − +++ printed 1:1 PLA textile, ++ reference PLA textile 1:4 +++ +++ Polyester textile, − reference Polyester textile, +++ +++ white 1:4 Polyester textile, +++ +++ white 1:1 Hemp textile, −− reference Hemp textile 1:4 − + Hemp textile 1:1 − ++ Polyester NW, +++ reference Polyester NW 1:4 +++ NA.sup.1) .sup.1)NW not washed since NW falls apart more easily than textiles
(49) The study shows that fatty PEC composition OC-D is compatible with various textiles since they become hydrophobic and stiff and that the hydrophobicity remains after wash.
(50) After the above presented test, a broader material study was undertaken using 5 washing cycles according to Method 4. See the results in Table 5. Hydrophobicity in relation to stiffness is shown in
(51) TABLE-US-00007 TABLE 5 Different textiles and nonwovens treated with PEC composition OC-D and washed according to Method 4. The hydrophobicity was evaluated according to Method 5. Material and the dilution (OC-D: Before After After After water) used wash 1 wash 2 washes 5 washes Linen textile, −− reference Linen textile 1:4 +++ ++ ++ − Linen textile 1:1 +++ ++ ++ ++ Cotton textile, −− green, reference Cotton textile, +++ ++ ++ − green 1:4 Cotton textile, ++ − − − green 1:1 Cotton textile, + white, reference Cotton textile, ++ +++ − − white 1:4.sup.1) Cotton textile, − +++ +++ ++ white 1:1.sup.1) Cotton textile, − printed Cotton textile, ++ ++ ++ − printed 1:4 Cotton textile, +++ ++ ++ ++ printed 1:1 PLA textile, ++ reference PLA textile 1:4 +++ +++ +++ +++ PLA textile 1:1 +++ ++ ++ ++ Polyester textile, − reference Polyester textile +++ ++ ++ − 1:4 Polyester textile +++ +++ +++ +++ 1:1 Hemp textile, −− reference Hemp textile 1:4 − + − − Hemp textile 1:1 − ++ ++ + Viscose NW, −− reference Viscose NW 1:4.sup.1) +++ +++ +++ NA Viscose NW 1:1.sup.1) +++ +++ ++ NA Polyester NW, +++ reference Polyester NW 1:4.sup.1) +++ +++ +++ NA Polyester NW 1:1.sup.1) +++ +++ +++ NA Viscose NW, rug ++ type, purple, reference Viscose NW, rug +++ +++ +++ NA type, purple 1:4.sup.1) Viscose NW, rug ++ − − NA type, purple 1:1.sup.1) .sup.1)Only washed two times since it is nonwoven and falls apart more easily than textiles.
(52) Experiment 7—Influence of the Hydrophobicity from different Fats/Oils/Fatty Acids/Resins included in the Fatty PEC Composition
(53) A scan of different oils, fatty acids, resins and salts was performed, see
(54) 100% viscose nonwoven was treated with fatty PEC compositions consisting of PEC and RO, CO, S2 and ESBO with the ratio PEC:oil 1:0.5 according to Method 6. The fatty PEC compositions were produced according to Method 1. The hydrophobicity was tested according to Method 5. From previous tests, it was shown that the hydrophobicity develops over time. None of the fatty PEC compositions with RO, CO and S2 was hydrophobic day 0, but PEC:ESBO was and the treated material kept a droplet of water on the surface for around 1 s. Day 1, the material treated with the fatty PEC compositions with PEC and RO, CO, S2 and ESBO gave varying hydrophobicity on the material, see
(55) Among tested compounds lecithin gave rise to a very hydrophobic NW material. Already after one day it showed ++ to +++ (see
(56) Experiment 8—Study of the Compatibility between PEC Composition with PEC and RO, CO, S2 and ESBO and Various Textile and NW Material
(57) Four fatty PEC compositions including fatty compounds RO, CO, ESBO and S2 with the ratio PEC:oil 1:0.5 were produced according to Method 12 and then tested on three different fabrics (the formulations were diluted to 1 wt % prior treatment and used according to Method 2). The treated material were washed according to Method 4. See Table 6 for the hydrophobicity determined according to Method 5.
(58) TABLE-US-00008 TABLE 6 Hemp, polyester and PLA textiles were treated with fatty PEC compositions including different oils, all with ratio PEC:oil 1:0.5. Hydrophobicity was detected before wash and after one, three and five washes. Grades of hydrophobicity are according to Method 5. Hydrophobicity Material and Before After After 3 After 5 treatment wash 1 wash washes washes 100% Hemp Untreated −− PEC:RO + to ++ + − −− PEC:CO + + − −− PEC:S2 + to ++ + − −− PES:ESBO + to ++ + − −− 100% Polyester Untreated − PEC:RO +++ ++ ++ ++ PEC:CO ++ to +++ + to ++ ++ ++ PEC: S2 +++ ++ to +++ ++ to +++ +++ PES:ESBO +++ +++ ++ to +++ +++ 100% PLA Untreated +++ PEC:RO +++ +++ +++ +++ PEC:CO +++ +++ +++ +++ PEC:S2 +++ +++ +++ +++ PES:ESBO +++ +++ +++ +++
(59) The study shows that various fatty PEC compositions give rise to hydrophobic textiles and that the hydrophobicity remains after wash.
(60) Experiment 9—Investigation of Hydrophobicity from PEC Composition Comprising of PEC, Water Soluble Plasticizer and Oil
(61) In order to increase the softness of the fatty PEC composition treated NW material and maintain hydrophobicity, four new fatty PEC compositions were developed containing additional water soluble plasticizer as follows:
(62) To 50 g of OC-B was added 0.375 g SO according to method 1 (OC-B_SO_0.375)
(63) To 50 g of OC-B was added 0.75 g SO according to method 1 (OC-B_SO_0.75)
(64) To 50 g of OC-B was added 0.375 g S2 according to method 1 (OC-B_S2-0.375)
(65) To 50 g of OC-B was added 0.75 g S2 according to method 1 (OC-B_S2_0.75)
(66) 100% viscose nonwoven was treated with the four formulations according to Method 6. For NW treated with OC-B_SO_0.375 and OC-B_SO_0.75, the material was hydrophilic at day 0 but already after two days the droplets stayed on the material for more than ten minutes (+++ according to method 5).
(67) For NW treated with OC-B_S2_0.375, after 2 days, the droplets only stayed for some seconds (+ according to method 6), while NW treated with OC-B_S2_0.75, after 2 days, droplets stayed on the material up to one minute (++ to+++ according to method 5)
(68) Experiment 10—The Influence of Fatty PEC Composition on Mechanical Properties
(69) According to
(70) TABLE-US-00009 TABLE 7 Dry and wet mechanical properties for nonwoven treated with various fatty PEC compositions. DRY PROPERTIES WET PROPERTIES (100% viscose NW) (100% biobased NW) Tensile Tensile Various Strain stiffness Strain Tensile stiffness fatty PEC @ peak index @ peak index index compositions (%) stadv (Nm/g) stadv (%) stadv (Nm/g) stadv (Nm/g) stadv Untreated, 16.4 2.5 170.3 11.9 17.7 2.7 1.4 0.1 22.5 3.3 Ref OC-C 12.9 1.0 891.7 196.5 18.9 3.0 3.4 0.2 102.5 6.4 OC-D 11.0 1.9 1053.3 222.8 31.6 6.2 3.7 0.3 102.7 21.2 PEC:RO 10.5 1.7 1148.4 230.1 18.8 2.5 2.9 0.3 98.4 16.3 1:0.5 PEC:CO 9.5 1.6 964.9 278.0 22.1 1.4 3.1 0.2 75.8 20.9 1:0.5 PEC:ESBO 11.7 2.4 990.6 223.8 20.3 3.3 2.8 0.2 78.4 12.2 1:0.5 PEC:S2 1:0.5 13.1 0.8 888.2 217.1 19.1 3.3 3.0 0.3 67.4 16.6 PEC:lecithin 2.7 0.5 469.1 122.3 14.8 1.8 2.2 0.2 88.4 26.0 1:0.5 OC-E 4.6 1.4 1181.8 436.3 17.3 3.9 3.8 0.2 125.1 28.2 OC-F 14.61 1.4 650.2 157.7 17.6 1.7 2.9 0.2 89.4 21.3 OC-G 12.7 2.0 752.2 281.9 20.5 1.4 3.4 0.2 85.6 12.3 PEC:SEH 77 6.6 2.1 635.5 236.0 19.1 3.1 3.0 0.5 81.7 26.5 7P 1:0.5 PEC:SEH 77 4.7 1.9 583.7 175.4 16.3 2.7 2.7 0.3 84.8 27.4 30P 1:0.5
(71) Based on the results summarized in Table 7 it can be concluded that the various fatty PEC compositions contribute to various mechanical properties, among which one can choose depending on the application.
Example 11—Performance Stability of Aged Fatty PEC Compositions
(72) In order to examine the performance stability of fatty PEC compositions, tensile tests were conducted according to Method 8 for NWs treated with aged and freshly prepared fatty PEC compositions OC-D and PEC:S2 1:0.5 (produced according to method 13) See Table 8 for results.
(73) TABLE-US-00010 TABLE 8 Wet properties of NW treated with freshly prepared and aged fatty PEC compositions WET PROPERTIES (100% biobased NW) Treatment with Tensile freshly prepared stiffness and aged fatty Tensile index index PEC composition (Nm/g) stadv (Nm/g) stadv Untreated, Ref 1.4 0.1 22.5 3.3 OC-D, freshly 3.7 0.3 102.7 21.2 prepared OC-D 2.8 0.3 76.1 30.6 30 days at 50° C. OC-D 3.0 0.4 105.6 34.1 45 days at 40° C. PEC:S2 1:0.5, 3.0 0.3 67.4 16.6 freshly prepared PEC:S2 1:0.5 3.0 0.2 70 17.6 30 days at 50° C.
(74) Table 11 shows that NWs treated with aged formulations compared to freshly prepared give an acceptable variation in mechanical properties. Hydrophobicity remains intact in all cases.
(75) Experiment 12—Viscosity Study Over Time for Various Fatty PEC Compositions
(76) Viscosity for fatty PEC compositions OC-D and PEC:S2 1:0.5, produced according to Method 12, was followed over time at 23° C., 40° C. and 50° C. From tables 9-12 it is concluded that viscosity change over time and temperature is acceptable.
(77) TABLE-US-00011 TABLE 9 Viscosities for PEC composition OC-D at 23° C. OC-D (23° C.) Day 200 150 100 50 10 6 rpm 1 1295 1367 1463 1835 2219 2399 mPas 37 1016 1299 1469 n/a n/a n/a mPas 91 1187 1267 1385 n/a n/a n/a mPas
(78) TABLE-US-00012 TABLE 10 Viscosities for PEC composition OC-D at 40° C. OC-D (40° C.) Day 200 150 100 50 10 6 rpm 45* 1076 1143 1247 1463 2159 2599 mPas *Acclimatized at 23° C. for 1 day before measurement.
(79) TABLE-US-00013 TABLE 11 Viscosities for PEC composition OC-D at 50° C. OC-D (50° C.) Day 200 150 100 50 10 6 rpm 30* 989 1039 1133 1403 2159 2599 mPas *Acclimatized at 23° C. for 1 day before measurement.
(80) TABLE-US-00014 TABLE 12 Viscosities for PEC composition PEC:S2 1:0.5 at 23° C. and 50° C. 23° C. 50° C. Day 200 150 100 200 150 100 1 1202 1259 1337 mPAs 9 950 1004 1086 mPAs 29* 881 947 1043 mPAs *Acclimatized at 23° C. for 2 days before measurement.
(81) Summary of Experiments 1-12
(82) Using PEC as an emulsifier for oils/fats/fatty acids results in stable emulsions/dispersions. When combining oils and PEC, the result is a fatty PEC composition that can be used as hydrophobic binder/additive for nonwoven, woven, textile and fiber based materials with durable hydrophobicity.
(83) Fatty PEC compositions with sunflower oil is outstanding when it comes to transferring hydrophobicity from the fatty PEC composition to materials. The hydrophobicity appears fast (already one day after treatment) and is durable (lasts for several washes of treated fabric and NW) when applied on several different fabrics and NWs, both of natural and synthetic origin. Tall oil fatty acid (S2) is another composition that transfers its hydrophobicity to fabrics and NWs. It also showed durable hydrophobicity on for example PES fabric. Example of oils comprised in the fatty PEC composition that show hydrophobicity already the same day as treated are ESBO and stand oils of soy bean. Fabrics treated with Span 80 did not show any hydrophobicity the first days after treatment, but one week after treatment it became hydrophobic. Interestingly, Span 80 is partly water soluble.
(84) It has also been shown that various fatty PEC compositions contribute to various mechanical properties, among which one can choose depending on the application. For example, sunflower oil can be the fatty compound comprised in the PEC composition when durable hydrophobicity is desired for a certain material, stand oils can be the fatty compound comprised in the PEC composition when instant hydrophobicity is needed and Span 80 can be the fatty compound comprised in the PEC composition for applications where one week delayed hydrophobicity is required.
(85) Experiments 13-14—Study of the Ability for PEC Compositions to be used as an Additive in Wet End Paper Making
(86) To evaluate the ability of the fatty PEC composition to transfer hydrophobic properties to fibers in a fiber suspension, paper sheets were produced where non-fatty PEC composition and fatty PEC composition were added in the wet end of the paper process. The formed paper sheets were evaluated with tensile tests, contact angle and Gurley.
(87) Equipment used in Experiments 13-14
(88) Below, all equipment used in experiments 13-14 is listed. pH in formulations and paper suspension was measured with pHenomenal pH1000H from VWR with Hamilton Polilyte Lab Temp BNC electrode (calibrated with buffers pH 4, 7 and 10). Homogenization of formulations in lab scale was done using IKA T25 digital Ultra-Turrax. Pulp suspension was created using a pulper Tico 732 Hengstler from PTI Austria. Paper sheets were produced in lab scale using Rapid-Kothen sheet former type RK-2A. Stirring of formulations and pulp suspensions was done with an overhead stirrer from IKA (either Eurostar digital IKA-Werke or IKA RW28 basic) together with a propeller. Additional drying of papers from Rapid Kothen was done in an oven from Termaks (suspended with clamps). Tensile tests were conducted using Testometric M250-2.5AT (machine capacity 2.5 kN) together with Wintest Analysis software. Contact angle was measured using PGX Serial 50585 from FIBRO Systems AB together with the software The PocketGonimeter Program verison 3.3 Gurley was measured using L&W Densometer (Type: 6_4, No.: 2241) from Lorentzen & Wettre.
(89) Chemicals used in Experiments 13-14
(90) Below, all chemicals used in experiments 13-14 are listed.
(91) TABLE-US-00015 Producer/ Chemical name Commercial name Distributor 1,2-Benzisothiazol-3(2H)-one, Nipacide BSM Clariant 2-methyl-2H-isothiazol-3-one Carboxymethyl cellulose FinnFix 5 CP Kelco Chitosan Chitosan 90/100/A1 Kraeber Citric acid mono hydrate Citronsyra Mono E33 Univar AB 8-80M LT Sunflower oil Sunflower oil 745100 AAK
(92) Abbreviations used in Experiments 13-14
(93) Below, all abbreviations used in experiments 13-14 are listed.
(94) TABLE-US-00016 CMC Carboxymethyl cellulose OC-C 2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 0.2 wt % Nipacide BSM produced according to Method 19 OC-E 2 wt % chitosan 90/100/A1, 2 wt % Finnfix 5, 12 wt % citric acid mono hydrate, 2 wt % sunflower 745100 (from AAK), 0.2 wt % Nipacide BSM produced according to Method 20 PEC Polyelectrolyte complex
(95) Methods used in Experiments 13-14
(96) Below, all methods used in experiments 13-14 are listed. Method 14: Pulp suspension consisting of sodium hydrogen sulfate bleached CTMP fibres (mean fibre length 1.2-1.5 mm) from Rottneros was prepared in 18-22° C. tap water and diluted to 0.5 wt %. The total amount (40 l) was divided to 2.5 l aliquots and the pH was adjusted to 5.5-6.5 with citric acid solution (citric acid mono hydrate:tap water, 1:2) in every batch, prior use. The strength system (i.e. PEC composition) was then added to the pulp suspension in different amounts and stirred vigorously with a propeller 10 min before the sheet forming was started. The pH was controlled 1-2 times during these 10 min and adjusted to <6.5 if it had risen. Method 15: Paper sheets were produced using Rapid Köthen sheet former and then dried for 8 min at 92° C. under vacuum (about 100 kPa). The resulting sheets got a paper density of around 60 g/m.sup.2. Five sheets at each test point were made. In some cases, additional drying at 190° C. for 3 min in Termaks oven was performed. Method 16: Tensile test for dry papers were performed by using Testometric M250-2.5AT (pretension: 0.1 N, sample length: 100 mm, sample width: 15 mm, speed: 20 mm/min, Loadcell 0: 50 kgf) after aclimatiozation of test specimens at 23° C. and 50% RH for least 1 day. Three test specimen for each paper sheet was cut out and tested. Method 17: General description of production method for PEC composition without oil/fat as additive (100 g formulation): 1. Homogenize 71.8 g water and 2 g CMC Finnfix 5 with Ultraturrax T25 with speed 9000 rpm for 3 min. 2. Disperse 2 g chitosan in the CMC-solution. 3. Dissolve 12 g citric acid mono hydrate in 12 g water and add to the biopolymer solution. Homogenize using 12000 rpm for 3 min. 4. Add 0.2 g Nipacide BSM. Homogenize 1 min. Method 18: General description of production method for PEC composition including oil/fat as additive (100 g formulation): 1. Homogenize 69.8 g water and 2 g CMC Finnfix 5 with Ultraturrax T25 with speed 9000 rpm for 5 min. 2. Disperse 2 g chitosan in the biopolymer solution. 3. Dissolve 12 g citric acid mono hydrate in 12 g water and add to the CMC-solution. Homogenize using 12000 rpm for 5 min. 4. Add 2 g oil/fat to the mixture. Homogenize with speed 12000 rpm for 5 min. 5. Add 0.2 g Nipacide BMS. Homogenize 1 min.
(97) Experiment 13—Mechanical Performance and Contact Angle Measurements of Fatty PEC Composition Treated Paper
(98) Pulp suspension was made according to Method 14 and papers with and without PEC compositions (fatty and non fatty) were produced according to Method 16. Since the amount of PEC in relation to fibers is important, it was decided to add the two compositions (OC-C and OC-E) to the paper suspension so that the amount PEC to fibers became 1 and 0.5% (d/d). The formulations were diluted to 1 wt % based on PEC, to facilitate mixing of PEC into fiber suspension, prior to addition to the pulp suspension. Dry tensile tests were conducted using Method 16. The results are shown in Table 13.
(99) TABLE-US-00017 TABLE 13 Mechanical properties of papers produced with and without additions of OC-C and OC-E to the pulp suspension. Addition to fiber is calculated on the PEC solid content in the formulations. Increase Mean Stdav in Addition Mean Stdav Increase Mean Stdav Increase tensile tensile tensile to fiber tensile tensile in tensile final final in final stiffness stiffness stiffness (dry/dry) index index index strain strain strain index index index Formulation [%] [Nm/g] [Nm/g] [%] [%] [%] [%] [Nm/g] [Nm/g] [%] Ref 0 18.84 2.11 1.03 0.16 2800.54 221.34 OC-C 0.5 22.49 1.38 19.37 1.37 0.15 32.56 2666.31 172.43 −4.79 1 25.05 1.73 32.96 1.29 0.12 25.30 2885.23 194.37 3.02 OC-E 0.5 20.90 2.01 10.93 1.51 0.21 46.65 2489.97 228.75 −11.09 1 25.86 1.57 37.28 1.32 0.08 28.13 3175.22 157.44 13.38
(100) From Table 13 it is seen that addition of the fatty PEC composition OC-E results in higher increase in final strain than using only PEC OC-C as an additive when adding small amount of additive (0.5% d/d) in relation to fiber. Also, increase in tensile stiffness is larger for the largest amounts of additive in relation (1% d/d) to fiber for fatty PEC composition OC-E compared to only OC-C.
(101) A second trial where the compositions were added to the pulp suspension so that the amount of total solid content to fibers became 0.5 and 1% (d/d), instead of the PEC solid content to fibers as shown above. The formulations were diluted to 1 wt % based on total solid content, to facilitate mixing of PEC into fiber suspension, prior addition. Dry tensile tests were conducted using Method 15. The results are shown in Table 14.
(102) TABLE-US-00018 TABLE 14 Mechanical properties of papers produced with and without additions of OC-C and OC-E to the pulp suspension. Addition to fiber is calculated on the total solid content in the formulations. Increase Mean Stdav in Addition Mean Stdav Increase Mean Stdav Increase tensile tensile tensile to fiber tensile tensile in tensile final final in final stiffness stiffness stiffness (dry/dry) index index index strain strain strain index index index Formulation [%] [Nm/g] [Nm/g] [%] [%] [%] [%] [Nm/g] [Nm/g] [%] ref 0 18.84 2.11 1.03 0.16 2800.54 221.34 OC-C 0.5 20.96 0.78 11.22 1.10 0.08 6.69 2917.81 145.81 4.19 1 19.65 1.74 4.31 1.09 0.12 5.50 2726.42 153.53 −2.65 OC-E 0.5 20.10 0.72 6.71 1.13 0.08 10.00 2771.57 113.82 −1.03 1 20.84 2.02 10.61 1.15 0.10 11.88 2843.39 246.03 1.53
(103) From table 19 it is obvious that the increase in final strain is doubled for the fatty PEC composition OC-E compared to only OC-C. Based on the results from table 18 and 19, it is concluded that a small addition of fatty PEC composition OC-E is better than large addition when higher strain is needed for the material.
(104) Table 15 shows the dynamic contact angle over a period of 60 s for paper containing OC-C and fatty PEC composition OC-E as additive when 0.5% and 1% (d/d) additions to fiber was calculated on the PEC solid content.
(105) TABLE-US-00019 TABLE 15 Contact angles of paper produced with and without additions of OC-C and OC-E to the pulp suspension. Addition to fiber is calculated on the PEC solid content in the formulations. All three tests are done on the same sheet. Dynamic contact angle [°] Addition to fiber (dry/dry) Test 1 Test 2 Test 3 Formulation [%] 1 s 30 s 60 s 1 s 30 s 60 s 1 s 30 s 60 s Ref 0 <45 0 0 <45 0 0 <45 0 0 OC-C 0.5 101.7 <45 0 91.4 <45 0 99.1 0 0 1 81.2 0 0 73.6 0 0 75.4 0 0 OC-E 0.5 102.6 102.0 100.8 107.7 107.7 103.7 104.0 100.1 101.0 1 97.3 91.2 91.7 107.1 103.8 103.2 99.2 97.5 96.7
(106) Results in Table 15 show that using OC-C as additive to pulp suspension give relatively high initial contact angles but that the water is absorbed by the paper within 60 s. Using the fatty PEC composition OC-E as an additive to pulp suspension results in a hydrophobic paper that has an initial contact angle around 100° which is unaffected over at least 60 s.
(107) Experiment 14—Change in Air Permeability Imparted by the Fatty PEC Composition when Used as an Additive to Pulp Suspension
(108) Pulp suspension was made according to Method 13 and papers with fatty PEC compositions were produced according to Method 15. To determine the air permeability of the papers Gurley method was used and Gurley seconds for 100 cc was determined. Two paper sheets for each test point were measured at three different spots. The results are shown in table 16.
(109) TABLE-US-00020 TABLE 16 Gurley (100 CC) for papers produced with and without additions of OC-C and OC- E to the pulp suspension. Addition to fiber is calculated on the PEC solid content in the formulations. Gurley for 100 CC [gurley seconds] Addition to fiber Mean (dry/dry) Gurley Formulation Series [%] Sheet 1 Sheet 2 seconds stdav Ref 1a. 0 2.8 2.9 3.1 4.2 4.2 4.3 3.6 0.7 OC-C 10. 0.5 3.9 4.0 3.9 3.0 3.0 2.9 3.5 0.5 7. 1 3.1 3.0 3.0 2.7 2.7 2.7 2.9 0.2 OC-E 11. 0.5 3.7 3.7 3.7 3.0 3.0 2.9 3.3 0.4 8. 1 2.6 2.0 2.1 3.5 3.5 3.5 2.9 0.7
(110) From table 16 it can be concluded that there is no significant difference between untreated reference paper and paper where OC-C and fatty PEC composition OC-E are used as additive. Hence, the fatty PEC composition does not or slightly affects the air permeability.
(111) Summary of Experiment 13-14
(112) Experiments 14-15 show that the fatty PEC composition of the invention is a highly suitable wet end additive in paper making process, where both mechanical and surface properties can be affected.
(113) Materials treated with the PEC composition of the present invention need curing to develop the mechanical and hydrophobic properties meant through treatment. The curing can be done at temperatures between 20° C. and 200° C., preferably between 80° C. and 190° C., more preferably between 120° C. and 180° C. For reaching the best results, the curing temperature and time need to be optimized for each material and process.
(114) As will be understood by those skilled in the present field of art, numerous changes and modifications may be made to the above described and other embodiments of the present invention, without departing from its scope as defined in the appending claims. For example, the pulps may be any kind of pulp, i.e. mechanical pulp, thermo-mechanical pulp, chemo-mechanical pulp, sulphate pulp, sulphite pulp, bleached pulp, unbleached pulp, short-fiber pulp, long-fiber pulp, recycled fibers, mixtures of different pulp grades etc. The invention works irrespective of the kind of pulp chosen.
(115) The term paperboard is here used as wide term including all kinds of different cellulose-based board grades, e.g. paper board, cardboard, corrugated board, single or multiply board, folding boxboard, chipboard etc.
(116) While for the clarity reasons, the PEC compositions are described in the following claims only as binders for fiber based materials, textiles, woven and nonwoven materials (i.e. applied in the dry end of the paper making process), it is equally understood that they can act as strength additives in the wet end of the paper making process.
(117) Without exceeding the scope of the present invention, various acids employed in the synthesis of the PEC compositions (i.e. carboxylic acids, fatty acids, lignosulfonic acid, etc), may equally be used in their salt form.
(118) Various aspects and embodiments of the present invention are defined by the following numbered claims.