MONOBENZOATE ANALOGS USEFUL AS PLASTICIZERS IN PLASTISOL COMPOSITIONS

Abstract

Unique 3-PPB monobenzoate analogs useful as plasticizers in polymeric dispersions, such as plastisols, melt compounds, and adhesives among other applications. The analogs are structurally similar to and/or derived from 3-phenylpropyl benzoate and heretofore were not known for use in industrial applications, particularly not as a plasticizer in polymeric applications. Depending on the application, the advantages rendered by the use of the inventive monobenzoate analogs include, among other things, excellent solvating properties and rheology, low viscosity and significantly improved viscosity over time, comparable or improved Tg suppression, set and open times, as well as health, safety and environmental advantages, over traditional plasticizers.

Claims

1. A non-phthalate plasticizer for use in polymeric dispersions, comprising: 2-methyl-3-phenylpropyl benzoate, 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate, or benzyl 2-methyl-3-phenylpropanoate.

2. A plastisol composition comprising: a. a polymeric dispersion; and b. a plasticizer that is an analog of 3-phenylpropyl benzoate, selected from the group consisting of 2-methyl-3-phenylpropyl benzoate, 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate, or benzyl 2-methyl-3-phenyl-propanoate. wherein the analog is used alone as a primary plasticizer or as a secondary plasticizer in combination with other plasticizers, and wherein the analog provides comparable or better solvation and rheology characteristics and improved viscosity stability over that achieved with traditional high solvating or diluent plasticizers.

3. The plastisol of claim 2, wherein the polymeric dispersion is a PVC- or an acrylic-based polymer.

4. The plastisol of claim 3 wherein the plasticizer is present in amounts of about 70 phr.

5. A blend of plasticizers for use in plastisol compositions, comprising 2-methyl-3-phenylpropyl benzoate, 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate, or benzyl 2-methyl-3-phenylpropanoate, blended with another plasticizer that is a phthalate ester, a phosphate ester, an adipate, an azelate, an oleate, a succinate, a sebacate, a citrate, a trimellitate, a terephthalate ester, a 1,2-cyclohexane dicarboxylate ester, an epoxy plasticizer, a fatty acid ester, a glycol derivative, a sulfonamide, a sulfonic acid ester, a benzoate, a bioplasticizer, a chloroparaffin, a polyester, a hydrocarbon, a hydrocarbon derivative, or mixtures thereof.

6. A blend of plasticizers for use in plastisol compositions comprising 2-methyl-3-phenylpropyl benzoate, 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate, or benzyl 2-methyl-3-phenylpropanoate, blended with any of isononyl benzoate, isodecyl benzoate, 2-ethylhexyl benzoate, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, epoxidized soybean oil, PG disoyate, PG monosoyate, or mixtures thereof.

7. A blend of plasticizers for use in plastisol compositions comprising 2-methyl-3-phenylpropyl benzoate, 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate, or benzyl 2-methyl-3-phenylpropanoate, blended with a solid plasticizer that is sucrose benzoate, dicyclohexyl phthalate, triphenyl phosphate, glycerol tribenzoate, 1,4-cyclohexane dimethanol (CHDM) dibenzoate, pentaerythritol tetrabenzoate, an alkyl glycol ester, or mixtures thereof.

8. An adhesive composition comprising: a. a polymeric dispersion; and b. a plasticizer selected from the group consisting of 2-methyl-3-phenylpropyl benzoate, 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate or benzyl 2-methyl-3-phenylpropanoate, present in amounts ranging from about 1 to about 20%, wet.

9. The adhesive composition of claim 8, wherein the polymeric emulsion comprises polyvinyl acetate or vinyl acetate ethylene.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG. 1 shows initial, 1-day, 4-day, 7-day, 2-week and 4-week Brookfield viscosity data obtained for the inventive monobenzoate analog, HMCA benzoate (X-614), as compared to 3-PPB (X-613).

[0042] FIG. 2 shows viscosity aging in terms of the 7 day/Initial Viscosity Ratio for HMCA benzoate and 3-PPB.

[0043] FIG. 3 shows initial shear data for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0044] FIG. 4 shows 1-day shear data for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0045] FIG. 5 shows 4-day shear data for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0046] FIG. 6 shows 7-day shear data for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0047] FIG. 7 shows 4-week shear data for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0048] FIG. 8 shows a comparison of the initial shear data versus the 7-day shear data for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0049] FIG. 9 shows gel/fusion curves for two plastisols, one comprising HMCA benzoate and the other 3-PPB.

[0050] FIG. 10 shows a comparison of the initial, 1-day, 3-day, and 7-day Brookfield viscosities for the inventive monobenzoate analog, 2-phenylethyl 2-phenylacetate (X-616), and 3-PPB (X-613).

[0051] FIG. 11 shows initial shear data for two plastisols, one comprising 2-phenylethyl 2-phenylacetate and the other 3-PPB.

[0052] FIG. 12 shows 1-day shear data for two plastisols, one comprising 2-phenylethyl 2-phenylacetate and the other 3-PPB.

[0053] FIG. 13 shows 3-day shear data for two plastisols, one comprising 2-phenylethyl 2-phenylacetate and the other 3-PPB.

[0054] FIG. 14 shows 7-day shear data for two plastisols, one comprising 2-phenylethyl 2-phenylacetate and the other 3-PPB.

[0055] FIG. 15 shows gel/fusion curves for the 2-phenylethyl 2-phenylacetate and 3-PPB.

[0056] FIG. 16 shows initial, 1-day, 3-day and 7-day Brookfield viscosity data obtained for two plastisols, one comprising benzyl 3-phenylpropanoate (X-615) and the other 3-PPB (X-613).

[0057] FIG. 17 shows initial shear ramp results for two plastisols, one comprising benzyl 3-phenylpropanoate and the other 3-PPB.

[0058] FIG. 18 shows 1-day day shear ramp results for two plastisols, one comprising benzyl 3-phenylpropanoate and the other 3-PPB.

[0059] FIG. 19 shows 3-day day shear ramp results for two plastisols, one comprising benzyl 3-phenylpropanoate and the other 3-PPB.

[0060] FIG. 20 shows 7-day shear ramp results for two plastisols, one comprising benzyl 3-phenylpropanoate and the other 3-PPB.

[0061] FIG. 21 shows gel fusion results for two plastisols, one comprising benzyl 3-phenylpropanoate and the other 3-PPB.

[0062] FIG. 22 shows roll compatibility test results comparing benzyl 3-phenylpropanoate's performance with that of 3-PPB.

[0063] FIG. 23 shows initial viscosity response results comparing 3-PPB and the various inventive analogs of 3-PPB (HMCA benzoate (X-614), 2-phenylethyl 2-phenyl acetate (X-616), benzyl 3-phenylpropanoate (X-615)), to a traditional DEGDB/DPGDB diblend (KF850S, K-Flex® 850S) in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0064] FIG. 24 shows 1-day viscosity response results comparing 3-PPB and the various inventive analogs of 3-PPB to the traditional DEGDB/DPGDB diblend in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0065] FIG. 25 shows 3-day viscosity response data comparing 3-PPB and the various inventive analogs of 3-PPB to the traditional DEGDB/DPGDB diblend in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0066] FIG. 26 shows 7-day viscosity response results comparing 3-PPB and the various inventive analogs of 3-PPB to the traditional DEGDB/DPGDB diblend in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0067] FIG. 27 shows glass transition temperature (Tg) suppression results for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0068] FIG. 28 shows set times for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0069] FIG. 29 shows open times for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a copolymer adhesive emulsion at plasticizer levels of 5, 10 and 15%, wet.

[0070] FIG. 30 shows initial viscosity response results for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a homopolymer adhesive emulsion at plasticizer levels of 5, 10, 15 and 20%, wet.

[0071] FIG. 31 shows 1-day viscosity response results for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a homopolymer adhesive emulsion at plasticizer levels of 5, 10, 15 and 20%, wet.

[0072] FIG. 32 shows 3-day viscosity response results for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a homopolymer adhesive emulsion at plasticizer levels of 5, 10, 15 and 20%, wet.

[0073] FIG. 33 shows 7-day viscosity response results for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a homopolymer adhesive emulsion at plasticizer levels of 5, 10, 15 and 20%, wet.

[0074] FIG. 34 shows glass transition temperature (Tg) suppression results for 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend in a homopolymer adhesive emulsion at plasticizer levels of 5, 10, 15 and 20%, wet.

[0075] FIG. 35 shows set times for homopolymer adhesive emulsions comprising 3-PPB and the various inventive analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend at plasticizer levels of 5, 10, 15 and 20%, wet.

[0076] FIG. 36 shows open times for homopolymer adhesive emulsions comprising 3-PPB and the various analogs of 3-PPB as compared to the traditional DEGDB/DPGDB diblend at plasticizer levels of 5, 10, 15 and 20%, wet.

DETAILED DESCRIPTION OF THE INVENTION

[0077] The present invention is directed to analogs of the monobenzoate 3-PPB, which have been found to be surprisingly useful for a variety of applications as primary or secondary plasticizers, including, but not limited to, plastisols and adhesives. The analogs comprise 3-methyl-3-phenylpropyl benzoate (HMCA-benzoate), 2-phenylethyl 2-phenylacetate, benzyl 3-phenylpropanoate, and benzyl 2-methyl-3-phenylpropanoate, components not previously known or used as plasticizers in polymeric applications. The invention is also directed to polymeric compositions including without limitation plastisols, adhesives, paints and other polymeric coatings, sealants and caulks comprising the inventive 3-PPB analogs.

[0078] A preferred embodiment of the invention is HMCA benzoate in combination with a polymeric dispersion. Another preferred embodiment is 2-phenylethyl 2-phenylacetate in combination with a polymeric dispersion. Still another preferred embodiment is the use of the inventive analogs as secondary or diluent plasticizers in a blend with traditional plasticizers.

[0079] Structures for the inventive analogs as compared to 3-PPB are set forth below:

##STR00001##

[0080] The inventive monobenzoate analogs can generally be utilized as either primary plasticizers or as secondary plasticizers in blends with other plasticizers in numerous polymeric dispersions, often as a substitute or alternative for conventional diluent plasticizers having a higher VOC content or plasticizers that have poor solvating and rheology characteristics or viscosity stability.

[0081] The present invention is not restricted to any particular polymer, although the invention may be described in terms of vinyl polymers. Any of the known polymers that can be formulated into a plastisol, melt compound, injection molding, extrusion, or calendaring polymer, adhesive, paint, sealant or caulk can be used in combination with one of the novel 3-PPB analogs to prepare a low VOC content composition having comparable or improved performance properties as compared to traditional plasticizers, in accordance with the present invention.

[0082] Notably, applications for the plasticizers of the present invention include use with numerous thermoplastic, thermoset, or elastomeric polymers often as an alternative for conventional plasticizers. By way of example, the inventive monobenzoate analogs may be used to prepare a reduced viscosity PVC, PVC copolymer or acrylic-based plastisol in accordance with the present invention. The inventive analogs are also useful in waterborne and non-waterborne adhesive compositions comprising polyvinyl acetate homo- and co-polymers.

[0083] Acrylic polymer compositions for which the inventive monobenzoate analogs are useful include various polyalkyl methacrylates, such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, or allyl methacrylate; or various aromatic methacrylates, such as benzyl methacrylate; or various alkyl acrylates, such as methyl acrylate, ethyl acrylate, butyl acrylate, or 2-ethylhexyl acrylate; or various acrylic acids, such as methacrylic acid and styrenated acrylics.

[0084] In addition to PVC, PVC copolymers and acrylic plastisols, the inventive monobenzoate analogs have utility for other polymeric compositions, both waterborne and non-aqueous, including but not limited to various homopolymers and copolymers comprising acrylics, vinyl acetate ethylene, vinylidene chloride, diethyl fumarate, diethyl maleate, or polyvinyl butyral; polyurethanes and copolymers thereof; polysulfides; cellulose nitrate; polyvinyl acetate and copolymers thereof; polyacrylates, methacrylates, styrene acrylates, and copolymers thereof; polychloroprenes; nitriles; polyamides.

[0085] Other polymers for which the inventive monobenzoate analogs may be useful as a plasticizer include epoxies, phenol-formaldehyde types; melamines; and the like. Still other polymers will be evident to one skilled in the art. Use of the inventive 3-PPB analogs is not meant to be limited to any particular polymer or polymer composition.

[0086] For purposes of the invention, “plastisol” means a liquid polymer composition comprising a particulate form of at least one non-crosslinked organic polymer dispersed in a liquid phase comprising a plasticizer for the polymer. As used in the invention, “plastisol” also means and includes an “organosol” that is a plastisol in which solvents, such as liquid hydrocarbons, ketones, or other organic liquids, are used in amounts greater than about 5 wt. % to control viscosity and other properties of a plastisol.

[0087] As used herein, “high solvator” or “high solvating” is a term that describes the plasticizer's efficiency in penetrating, thickening, and gelling solid plastisol before full physical properties are developed. All the plasticizer is absorbed into the PVC of a plastisol at lower temperatures than general purpose plasticizers, thus facilitating a faster formation of a homogenous phase.

[0088] As used herein, “inventive analog” or “inventive monobenzoate analog” or “3-PPB analog” are interchangeable and mean the novel compounds of the invention that are structurally similar to and/or derived from the monobenzoate 3-PPB as set forth herein, which heretofore have not been used as plasticizers as described herein.

[0089] The novel monobenzoate analogs of the present invention may be used as a low VOC substitute for other diluent plasticizers, such as isodecyl benzoate, or as alternative plasticizers for various traditional polymer dispersions, including without limitation vinyl applications.

[0090] The total amount of the inventive monobenzoate analogs used in any particular polymeric dispersion would range broadly depending on the particular polymer, the characteristics of the polymer and other components, the process, the application or use and the results desired. The total amount used would range broadly depending on the application, generally from about 1 to about 300, desirably from about 10 to about 100, and preferably from about 20 to about 80 parts by weight for every 100 total parts by weight of the one or more thermoplastic, thermoset, or elastomeric polymers, including without limitation those identified above.

[0091] For HMCA benzoate, a particularly preferred embodiment for a plastisol would include amounts of plasticizer ranging from 10 to 70 phr.

[0092] In adhesives, plasticizers range in amounts from about 1 to about 50 wt. %, preferably from about 5 to about 20 wt. %, based on the weight of the wet adhesive, also referred to as “%, wet”. As an example, preferred embodiments for an adhesive include 10 wt. % in homopolymer polyvinyl acetate and 5 wt. % in vinyl acetate ethylene copolymers. As a general rule, the harder the polymer (higher Tg), the more plasticizer required.

[0093] Useful amounts are described herein and set forth in the examples. It is expected that one skilled in the art would be able to arrive at additional acceptable amounts based on the intended use and desired performance in the particular polymeric application.

[0094] The inventive plasticizers may be, but are not required to be, blended with various other conventional plasticizers to enhance or augment properties of polymeric compositions, including but not limited to improving compatibility and processability in a plastisol and enhancing solvating power. The inventive analogs are particularly useful to compatibilize poor solvating conventional plasticizers with a polymer. Some of these conventional plasticizers have been described herein and include, but are not limited to, various phthalate esters, phosphate esters, adipate, azelate, oleate, succinate and sebacate compounds, citrates, trimellitates, terephthalate esters such as DOTP, 1,2-cyclohexane dicarboxylate esters (such as Hexamoll® DINCH®), epoxy plasticizers, fatty acid esters, glycol derivatives, sulfonamides, sulfonic acid esters, benzoates, bioplasticizers, such as PG disoyate and PG monosoyate, chloroparaffins, polyesters, and various other hydrocarbons and hydrocarbon derivatives that are often utilized as secondary plasticizers, such as epoxidized soybean oil, and the like.

[0095] Monobenzoates, such as isononyl benzoate, isodecyl benzoate, and 2-ethylhexyl benzoate, as well as 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB™, an Eastman trademark) can also be blended with the inventive monobenzoate analogs, or any of these can be replaced with the advantage that less is needed to achieve processable viscosity and rheology, improve gel/fusion and reduce volatility.

[0096] The inventive monobenzoate analogs may also be blended with solid plasticizers such as sucrose benzoate, dicyclohexyl phthalate, triphenyl phosphate, glycerol tribenzoate, 1,4-cyclohexane dimethanol (CHDM) dibenzoate, pentaerythritol tetrabenzoate, and alkyl glycol esters.

[0097] Other suitable plasticizers for use in combination with the inventive analogs will be known to one skilled in the art.

[0098] The inventive monobenzoate analogs may also be combined with or include various amounts of conventional additives such as oils, diluents, antioxidants, surfactants, heat stabilizers, flame retardants, surfactants, blending resins, waxes, solvents and the like, depending on the particular application or polymeric dispersion. Additives amounts can generally vary widely and often range from about 0.1 to about 75 parts by weight for every 100 parts by weight of the plastisol composition.

[0099] For vinyl applications, there are two different methods of fusing: plastisols and melt compounding. A plastisol is a liquid dispersion of PVC (or other polymer) in plasticizer, which may be heated as a spread coating, fused in slush molding, dip molding or rotationally molded. The plastisols of the invention may be compounded by simple mixing or blending, followed by de-aerating in most instances. Melt compounding is a process that uses heat and pressure while mixing to fuse vinyl (or other polymer). Its overall purpose is to combine the polymer and plasticizer into a homogeneous material which can be formed through a calendar, extruder or injection mold.

[0100] Exemplary formulations and preparation steps for simple basic starting plastisols and basic adhesive emulsions are set forth in the examples; however, the invention is not limited to these formulations. By way of example only, a typical basic plastisol is set forth below:

TABLE-US-00001 Dispersion Resin, PVC 100 phr Plasticizer 70 phr Ca/Zn stabilizer 3 phr

[0101] By way of example only, a typical packaging adhesive is set forth below:

TABLE-US-00002 Homopolymer or Copolymer 100 parts Plasticizer 0-30 parts Water 0-20 parts PVOH (88%) hydrolyzed 0-100 parts Fillers 0-100 parts Additives (wetting agents, defoamers) 0.10 to 0.5 parts

[0102] The inventive monobenzoate analogs provide a lower VOC content alternative over secondary and diluent type plasticizers and, depending on the application, provide comparable or better compatibility, viscosity stability, and rheology, among other advantages. In many instances, the inventive monobenzoate analogs may outperform industry standard plasticizers, including traditional and newer dibenzoate blends. Many traditional plasticizers have either high solvating properties or low viscosity, but not both. Surprisingly, the inventive monobenzoate analogs strike a good balance between high solvating power, better rheology and lower viscosity even when used alone.

[0103] For adhesives, the inventive monobenzoate analogs provide comparable or better compatibility, viscosity stability and response, rheology, set time, open time, Tg suppression, and MFFT, among other advantages, when compared to traditional dibenzoate plasticizers typically used in adhesives. The inventive monobenzoate analogs may be particularly useful as a plasticizer when considering the use of harder polymers as alternatives to softer polymers in a variety of low VOC formulations.

[0104] There are a large variety of uses for the plastisols and melt compounds of the invention, including but not limited to resilient flooring, wear layers, wall coverings, toys, gloves, and leather and textile applications.

[0105] The inventive monobenzoate analogs may be used in adhesive compositions, sealants and caulks for a large variety, including without limitation packaging glues, adhesive assembly, labeling, laminates, envelopes, food packaging, wood glue, construction adhesives, transportation product assembly, electronic product assembly and pressure sensitive adhesive (PSA) applications, although this list is by no means exhaustive.

[0106] Still other uses for the inventive monobenzoate analogs will be evident to one skilled in the art.

[0107] A variety of methods that may be used to prepare the inventive analogs are known to one skilled in the art. The inventive analogs are not limited to any particular method of preparation.

[0108] The invention is further described by the examples set forth herein, but is not limited thereby.

Examples

[0109] Experimental Methodology

[0110] Plastisol and Vinyl Preparation:

[0111] The plastisols were prepared in a Hobart Model N-50 mixer. A ten minute mix at speed one (1) was used. A high speed disperser was also used to prepare other plastisols evaluated employing a ten minute mix at 1000 RPM's. All of the plastisols were degassed at 1 mmHg until as completely air free as possible.

[0112] Tests/Evaluations

[0113] The goal was to determine the basic performance parameters of the inventive plasticizers. Tests demonstrating processability (viscosity, viscosity stability, rheology, and gel/fusion) were utilized. Unless otherwise indicated in specific examples, the general tests and/or methodologies described below were used in the examples. The tests and methods are known to one skilled in the art.

[0114] Test Methods

[0115] AR2000 Gel/Fusion Method:

[0116] A 25 mm steel plate geometry was used in combination with the ETC (environmental test chamber). A gap of 400 μm was used. The temperature was ramped at a rate of 5° C./min. from 40° C. to 200° C. using a controlled strain of 2% and an angular frequency of 1 rad/sec.

[0117] AR2000 Shear Method, Steel Plate, Plastisol:

[0118] A 20 mm steel plate geometry with Peltier plate and gap set to 200 μm was used. A dime-sized amount of plastisol was placed on the Peltier plate. The shear ramp was run at 25° C. from 0 to 1000 s.sup.−1 over five minutes.

[0119] Brookfield Viscosity Method:

[0120] The Brookfield viscosity was tested using the RVDVII+Pro Viscometer. A 30 second reading at 20 RPM's was taken; temperature was 23±1° C.

[0121] Roll Compatibility Test:

[0122] A strip of vinyl was tightly rolled with yellow legal absorbent paper then placed in an oven at 60° C. for three days. Compatibility was judged on the degree of exudation in sum.

[0123] Sample Preparation:

[0124] Prepared a ˜400 g batch. Solids were added to liquids while mixing on low speed in Hobart or Kitchen Aid mixer. Mixed total of 10 minutes, (wiped solids down after 5 minutes). Degassed for 15 minutes.

[0125] Neat Plasticizer Volatility:

[0126] TGA—approximately 10 mg of sample was placed into a platinum pan. The pan was quickly ramped to 110° C. and then held isothermally at that temperature for four hours under 160 ml/min air flow. Oven—ASTM D2369.

[0127] Materials

[0128] The following materials are used in the examples:

[0129] X-613—3-phenylpropyl benzoate or 3-PPB

[0130] X-614 —HMCA benzoate

[0131] X-615—benzyl 3-phenylpropanoate

[0132] X-616—2-phenylethyl 2-phenylacetate

[0133] Neat Plasticizer Properties—Volatility and Viscosity

[0134] Preliminarily, the volatilities of the X-600 series plasticizers referenced above were determined via both ASTM D2369 and TGA (four hour isothermal hold at 110° C. under air). The ASTM D2369 results are shown in Table 1 below. X-614 had the lowest volatility of the 600 series plasticizers by both methods of testing. Using the TGA method, X-614 had almost 10% less weight loss after four hours than the other plasticizers (X-613, X-615 and X-616) of the series, which had comparable weight loss. (results not shown). X-615 and X-616 had moderately high volatility relative to X-613 and X-614, while their weight losses as evaluated by the TGA method were similar.

TABLE-US-00003 TABLE 1 ASTM D2369 Volatility of X-600 Series Plasticizers VOC Experimental # Chemical Name Lot Number(s) (wt. %) X-613 3-Phenylpropyl benzoate AR060214C, 3.3, 3.7 EH042914C X-614 2-Methyl-3-phenylpropyl CS071614A 2.8 benzoate X-615 Benzyl-3-phenylpropanoate CS080414B 5.6 X-616 2-Phenylethyl-2-phenylacetate EH080614A 4.5

[0135] The neat plasticizer viscosities (50 RPM) are shown below in Table 2. X-614 had the highest viscosity of the series.

TABLE-US-00004 TABLE 2 Viscosities of Neat Plasticizers Experimental # Viscosity (mPa .Math. s) Temp. (° C.) X-613 34.4 24.9 X-614 48.8 24.8 X-615 26.4 24.8 X-616 28.8 25.0

Example 1—Basic Plastisol Evaluations (HMCA Benzoate)

[0136] Examples 1, 2 and 3 show the efficacy of the inventive monobenzoate analogs utilizing a basic starting plastisol formulation described below:

Basic Plastisol Formulation

[0137]

TABLE-US-00005 Material PHR Dispersion Resin, K76, Geon 121 A 100 Plasticizer 70 Ca/Zn stabilizer, Mark 1221 3

[0138] Processability

[0139] The inventive monobenzoate analog HMCA benzoate (X-614) was compared to 3-PPB (X-613). HMCA benzoate is very similar in structure to 3-PPB, with only the addition of a methyl group.

[0140] FIG. 1 and Table 3 below shows initial, 1-day, 4-day, 7-day, 2-week or 4-week viscosity data obtained for HMCA-benzoate (X-614), which compares favorably to 3-PPB (X-613) and reflects unexpectedly better viscosity stability.

TABLE-US-00006 TABLE 3 Brookfield Viscosity Measurements Viscosity (mPa .Math. s) X-613 X-614 Initial Temp (° C.) 23.0 23.1 Viscosity (mPa .Math. s) 778 1042 1-Day Temp (° C.) 23.5 23.4 Viscosity (mPa .Math. s) 1336 1380 4-Day Temp (° C.) 23.7 23.5 Viscosity (mPa .Math. s) 1980 1642 7-Day Temp (° C.) 23.5 23.6 Viscosity (mPa .Math. s) 2705 1818 14-Day  Temp (° C.) 23.8 23.4 Viscosity (mPa .Math. s) 4240 1920 28-Day  Temp (° C.) 23.5 23.8 Viscosity (mPa .Math. s) 6560 1955

[0141] FIG. 2 shows the viscosity aging ratio obtained by comparing the 7-day viscosity data with the initial viscosity for both X-613 and X-614. The results demonstrated that the initial viscosity results of the two plasticizers were similar, while the viscosity aging of the inventive monobenzoate analog X-614 was notably less than X-613, indicating that X-614 is much more stable over time. Viscosity control is a significant advantage in plastisol applications and X-614 offers an alternative for improved plastisol storage stability over other plasticizers.

[0142] These results reflect that HMCA benzoate (X-614) is a viable alternative to 3-PPB (X-613) for use in plastisol compositions. Unexpectedly, HMCA benzoate has low viscosity, comparable rheology, good solvating properties and improved viscosity stability when compared with 3-PPB. It is also lower in cost, making it a very desirable alternative.

[0143] Rheology and Gel/Fusion

[0144] The basic 70 phr plastisol formulation above was again utilized to compare 3-PPB (X-613) to HMCA benzoate (X-614) to evaluate rheology and gel/fusion. Rheology data (initial, 1-day, 4-day, 7-day and 4-week shear data) and gel/fusion curves were obtained as reflected in FIGS. 3-7, respectively. FIG. 8 is a comparative curve showing the initial shear versus 7 day shear values for both HMCA benzoate and 3-PPB.

[0145] As shear rate was increased, higher and higher viscosity was expected. While the initial shear (FIG. 3) was a little higher for the X-614 plastisol, the aging of the X-614 plastisol was once again shown to be lower than that of X-613, with X-613's shear ramp curve being greater than that of X-614 after four days. In short, viscosity for HMCA benzoate remained level over time, while 3-PPB increased over time. These results demonstrate that HMCA benzoate has a much better rheology profile than 3-PPB.

[0146] Gel fusion data illustrates the relative solvation characteristics of various plasticizers. FIG. 9 shows the results of the gel/fusion evaluation, which reflected very similar results for 3-PPB as compared to HMCA benzoate. The results show that X-613 displays slightly better gel fusion temperatures. X-614 was only slightly lower in solvation, yet still comparable to typical dibenzoate solvation efficiency.

[0147] Past experiments have demonstrated that 3-PPB is far more efficient than isodecyl benzoate (IDB, a monobenzoate diluent plasticizer) as a solvator, yet viscosity and rheology are not sacrificed. The present data demonstrated that HMCA benzoate is a very viable alternative for 3-PPB, as it behaves very similarly with regard to viscosity reduction and gel/fusion. There are some slight sacrifices with respect to solvating ability, but the significant improvement in viscosity stability provide for a very viable reduced cost alternative.

[0148] Overall, the results demonstrated that HMCA benzoate imparts a combination of excellent rheology and very good solvation properties to a basic plastisols formulation.

[0149] Roll Test.

[0150] A roll test was utilized to determine compatibility of X-614 in the basic plastisol formulation. (Results not shown.) Ratings were “0” for each day, indicating full compatibility.

[0151] The results above establish that HMCA benzoate is a compatible, high solvator having lower and more stable viscosity than 3-PPB, which make it suitable alone or in combination with other plasticizers for use in plastisol applications.

Example 2—Basic Plastisol Evaluation 2-Phenylethyl 2-Phenylacetate

[0152] Processability

[0153] The basic 70 phr plastisol formulation of Example 1 was also used in this evaluation.

[0154] FIG. 10 shows comparative initial, 1-day, 3-day, 7-day, 2-week, 3-week and 4-week viscosities for 3-PPB (X-613) and 2-phenylethyl 2-phenylacetate (X-616). X-616 is similar in structure to X-613, with the ester group shifted down one position further away from the aromatic ring. The data shows that the initial viscosities of X-616 and X-613 are similar, while the viscosity aging of the inventive X-616 plastisol is less than that of X-613. X-616's viscosity stability over time was much better than that obtained for 3-PPB, which provides an advantage in plastisol formulations. X-616's viscosity stability was not quite as good as that obtained for HMCA benzoate in Example 1, above, but it was still much improved over 3-PPB. Brookfield viscosity results are also shown in Table 4, below.

TABLE-US-00007 TABLE 4 Brookfield Viscosity Measurements X-613 Control X-616 Initial Temp (° C.) 24.0 23.2 Viscosity (mPa .Math. s 492 404 1-Day Temp (° C.) 23.5 23.2 Viscosity (mPa .Math. s) 782 516 3-Day Temp (° C.) 23.8 23.7 Viscosity (mPa .Math. s) 1090 608 7-Day Temp (° C.) 23.8 23.7 Viscosity (mPa .Math. s) 1422 708 15-Day  Temp (° C.) 23.3 24.1 Viscosity (mPa .Math. s) 3030 1388 21-Day  Temp (° C.) 23.9 24.0 Viscosity (mPa .Math. s) 3650 1788 28-Day  Temp (° C.) 23.6 23.8 Viscosity (mPa .Math. s) 5460 1915

[0155] Rheology and Gel/Fusion

[0156] The basic 70 phr plastisol formulation of Example 1 was also used to compare 3-PPB (X-613) to 2-phenylethyl 2-phenylacetate (X-616) to evaluate rheology and gel/fusion. Rheology data (initial, 1-day, 3-day, and 7-day shear data) was obtained as reflected in FIGS. 11-14, respectively. The results are very similar for the initial and one day scans, while the three and seven day scans show more shear thickening with the X-613 plastisol versus the X-616 plastisol above about 400 s.sup.−1. As shear rate was increased, higher and higher viscosity was expected. Like the X-614 results of Example 1, viscosity for 2-phenylethyl 2-phenylacetate (X-616) was higher initially than 3-PPB (X-613), but over time leveled off, while 3-PPB increased over time. These results show that 2-phenylethyl 2-phenylacetate (X-616) is comparable to 3-PPB (X-613) and has a better rheology profile.

[0157] Gel fusion data illustrates the relative solvation characteristics of various plasticizers. FIG. 15 shows the results of the gel/fusion evaluation, which reflected fairly similar results for 3-PPB (X-613) as compared to 2-phenylethyl 2-phenylacetate (X-616), which was only slightly lower in solvation characteristics.

[0158] Roll Test.

[0159] The roll test was utilized to determine compatibility of X-616 in the 70 phr plastisol formulation. (Results not shown.) The ratings were “0” for each day, indicating full compatibility.

[0160] The results above establish that 2-phenylethyl 2-phenylacetate is viable option for plastisols. It is a compatible solvating plasticizer with low viscosity characteristics, with the added bonus of unexpectedly lower and more stable viscosity over time than that achieved with 3-PPB. As such, it is suitable alone or in combination with other more traditional plasticizers used in plastisol applications.

Example 3—Basic Plastisol Evaluation—Benzyl 3-Phenylpropanoate

[0161] Processability

[0162] The basic 70 phr plastisol formulation of Example 1 was used in this evaluation. Brookfield viscosity measurements for X-613 and benzyl 3-phenylpropanoate (X-615) are shown in Table 5 below. X-615 is similar in structure to X-613, with the ester group shifted one space away from the benzyl ring.

TABLE-US-00008 TABLE 5 Brookfield Viscosity Measurements X-613 X-615 X-615 Description Control X-615 Remake 1 Remake 2 Initial Temp (° C.) 22.5 22.5 23.9 23.1 Viscosity (mPa .Math. s) 596 3190 1566 1684 Spindle 2 3 2 2 1-Day Temp (° C.) 22.3 22.2 24 23.3 Viscosity (mPa .Math. s) 856 1595 1782 995 Spindle 2 3 2 3 3-Day Temp (° C.) 22.2 22.4 23.9 25 Viscosity (mPa .Math. s) 1190 3330 1100 1995 Spindle 2 3 3 3 7-Day Temp (° C.) 23.5 23.7 23.9 23.6 Viscosity (mPa .Math. s) 1602 2190 1750 4965 Spindle 2 3 3 3 (99%)

[0163] The Brookfield viscosity results are also shown in FIG. 16.

[0164] The X-615 sample demonstrated unusual viscosity behavior, based on the choice of spindle, which had a very big impact on the viscosity results. Samples were remade to retest the viscosities and confirm the result. As shown in Table 6 below, a switch from spindle 2 to spindle 3 for one sample resulted in a viscosity decrease of over 50% at 1-day interval.

TABLE-US-00009 TABLE 6 Differences in X-615 Plastisol Viscosity from Spindle Change (1-Day Measurements) Sample ID Temp ° C. Viscosity (mPa .Math. s) Spindle X-615A 24.0 1782 2 X-615A 24.0 815 3

[0165] Rheology/Gel Fusion

[0166] The initial, 1-day, 3-day and 7-day shear ramp results are shown in FIGS. 17 through 20, respectively. The X-615 plastisol had consistently different (atypical) shear curve shapes than the plastisol comprising X-613.

[0167] The gel/fusion results of both plastisols are shown in FIG. 21. X-613 displayed slightly better gel/fusion temperatures, while X-615 had gel/fusion results more comparable to what is typically seen with dibenzoate blends. Even so, X-615 demonstrated acceptable gel/fusion results.

[0168] Roll Test.

[0169] The roll test was additionally utilized to determine the compatibility of X-615 in the plastisol formulation. The results, shown in FIG. 22, indicated that X-615 is not fully compatible with vinyl.

[0170] The X-615 plasticizer demonstrated unusual behavior in the plastisol application, particularly with regard to its spindle-dependent viscosity response and somewhat atypical shear rate curves. Although gel/fusion results demonstrated good solvation power, the roll test demonstrated that there are compatibility problems with vinyl. Even so, X-615's compatibility is still on par with or slightly better than that seen of DOTP or DINCH in a plastisol. As such, it may still present a viable plasticizer for use in vinyl in combination with other plasticizers.

[0171] The plastisol evaluations above (Examples 1-3) demonstrate the utility of the inventive monobenzoate analogs. Traditional diluent plasticizers are highly volatile, making them poor choices for use in plastisols, in view of increasing regulatory scrutiny. Typical plasticizers known to the industry often have excellent solvation or excellent rheology characteristics, but not both. The present inventive monobenzoate analogs with their lower volatility, good solvation and rheology characteristics and improved viscosity stability also provide a very suitable blending plasticizer alternative for use with traditional plasticizers.

Example 4—Adhesive Evaluation

[0172] Test Methods

[0173] Materials

[0174] K-Flex® 850S (a traditional DEGDB/DPGDB diblend)

[0175] X-613: 3-PPB

[0176] X-614: HMCA benzoate

[0177] X-615: benzyl 3-phenylpropanoate

[0178] X-616: 2-phenylethyl 2-phenylacetate

[0179] Polyvinyl acetate homopolymer: Pace™ 383 (manufactured by H. B. Fuller)

[0180] Vinyl acetate ethylene copolymer: Elvace® 735 (manufactured by H. B. Fuller)

[0181] Preparation:

[0182] Plasticizer was added to emulsion while mixing with a Jiffy blade at 750 RPM's. Total mixing time was ten minutes.

[0183] Brookfield Viscosity:

[0184] The Brookfield viscosity was tested using a RVDVII+Pro Viscometer. A 30 second reading at 20 RPM's was taken; temperature was 23±1° C.

[0185] DSC Glass Transition:

[0186] Twenty μL of emulsion was pipetted into a tared aluminum DSC pan with lid. The pan was allowed to dry in a 50° C. oven overnight, then reweighed to determine dry weight (approximately 10 mg). The lid was then placed on the pan and clamped shut. The DSC temperature was equilibrated at −40° C., then ramped at 5° C./min to 65° C. Glass transition was measured as the onset of Tg.

[0187] Open Time Method:

[0188] A 1.5″×14″ piece of 50 lb. unbleached Kraft paper was placed on a glass surface, with a 1″×14″ piece of Kraft clipped to its top, rolled back so that the bottom piece was left uncovered. The top piece was sandwiched between a #0 and #14 wire wound rod with the #0 on top. A small amount of adhesive was applied to the top of the bottom strip and a #20 wire wound rod metered out the adhesive over the entire strip. A timer was started, and at a specified time interval (with intervals of 5 seconds) the top strip was laminated to the bottom using the #0 rod. The strips were then peeled apart and assessed for adhesion and fiber tear. This process was repeated until a specific time interval was confirmed in duplicate as the last time interval to result in significant fiber tear/adhesion. Evaluations were performed blind.

[0189] Set Time Method:

[0190] Set time determinations were made using two strips of 50 lb. unbleached Kraft paper measuring 1″×14″ (top) and 1.5″×14″ (bottom). A small amount of adhesive was applied to the bottom strip, and a #20 wire wound rod metered the adhesive onto the bottom strip while a #16 wire wound rod (rubber banded to the #20) simultaneously pressed down the top strip. A timer was then immediately started and the strips were pulled apart until significant force was required to tear apart the strips and fiber tear was noted. Time at this point was recorded as the set time. A minimum of three repetitions were performed. Evaluations were performed blind.

[0191] X-613, X-614, X-615 and X-616 (as described above) were evaluated in both a copolymer (VAE, Elvace® 735) and homopolymer (PVAc, Pace™ 383) adhesive emulsions. K-Flex® 850S was also evaluated for comparison. Plasticizers were evaluated at levels of 5%, 10% and 15%, wet for the copolymer and levels of 5%, 10%, 15%, and 20%, wet, for the homopolymer. For the purposes of the evaluation, “wet” means the loading amount in weight percent (wt. %) of the plasticizer incorporated into the polymeric emulsion.

[0192] In both emulsion systems, the X-600 plasticizers tended to depress Tg more strongly than a traditional dibenzoate diblend (K-Flex® 850S). In the copolymer, the X-600 series plasticizers performed similarly in the other aspects of testing to the diblend. In the homopolymers, the viscosity suppression, set times, and open times were generally slightly poorer with the X-600 plasticizers than with the diblend, although performance was acceptable.

[0193] Copolymer Viscosity Response

[0194] The copolymer viscosity response results (Temp˜22-23° C.) for initial, 1-day, 3-day and 7-day are shown in FIGS. 23 through 26 and Table 7, below. The responses were all very similar showing good compatibility with the base copolymer.

TABLE-US-00010 TABLE 7 Copolymer Viscosity Response Data Viscosity (cP) Plasticizer Wt. % Initial 1-Day 3-Day 7-Day Blank 0 2005 2080 2020 2120 K-FLEX ® 5 3400 3530 3410 3680 850S 10 7070 7140 6960 7160 15 14920 14840 15440 14960 X-613 5 3400 3550 3530 3770 10 7280 7040 7220 7080 15 15920 16040 15660 15980 X-614 5 3420 3720 3720 4020 10 7320 7280 7300 7240 15 15000 15800 15180 15720 X-615 5 3510 3610 3460 3600 10 6960 7140 7100 7140 15 15800 16060 15960 15480 X-616 5 3620 3550 3570 3770 10 7160 7340 7240 7260 15 15500 15740 15800 15880

[0195] Table 8, below, shows viscosity data obtained for homopolymers.

TABLE-US-00011 TABLE 8 Homopolymer Viscosity Response Data Viscosity (cP) Plasticizer Wt. % Initial 1-Day 3-Day 7-Day Blank 0 3800 3740 3830 3760 K-FLEX ® 5 5790 5110 4530 4460 850S 10 5840 5980 6010 5870 15 8620 8540 8490 8020 20 11660 11980 11440 11500 X-613 5 4260 4170 4230 4300 10 5800 5740 5730 5860 15 7620 7680 7760 7630 20 11180 11180 11400 11380 X-614 5 4310 4360 4340 4420 10 5210 5510 5530 5570 15 7340 8260 8210 8190 20 11940 13000 12880 13200 X-615 5 3920 4180 4120 4250 10 5000 5290 5180 5290 15 7250 7340 7140 7210 20 10200 11740 10920 11000 X-616 5 4150 4170 4080 4140 10 5050 5340 5380 5320 15 7150 7440 7450 7560 20 11260 11980 11760 12000

[0196] Copolymer Glass Transition Temperature Suppression

[0197] The copolymer glass transition temperature results are shown in FIG. 27. While all of the X-600 series plasticizers were more effective in lowering glass transition temperature than the traditional DEGDB/DPGDB diblend (K-Flex° 850 S), X-615 and X-616 had the most dramatic effect across all concentration levels, indicating a more flexible polymer and more efficient plasticizer.

[0198] Copolymer Set and Open Times

[0199] The copolymer set times (FIG. 28) and open times (FIG. 29) demonstrated very similar performance among all plasticizers evaluated. Set time results demonstrate that the X-600 series plasticizers had similar bond formation time in the same polymeric adhesive as the traditionally used DEGDB/DPGDB diblend.

[0200] Homopolymer Viscosity Response

[0201] The homopolymer viscosity response results for initial through seven days are shown in FIGS. 30-33 and Table 8 above. X-614 behaved very similarly to the traditional diblend (K-Flex° 850S), while the other X-600 series plasticizers generally seemed slightly less efficient in increasing homopolymer viscosity. Still, the results show compatibility with the base polymer.

[0202] Homopolymer Glass Transition Temperature Suppression

[0203] The glass transition temperature suppression results for the homopolymers emulsion are shown in FIG. 34. X-613 and X-614 performed very similarly to the traditional diblend (K-Flex° 850S), while the X-615 and X-616 were notably more efficient in dropping Tg as was encountered with the copolymer evaluations.

[0204] Homopolymer Set and Open Times

[0205] The homopolymers set times, shown in FIG. 35, indicate that at levels up to 15% of X-600 series are notably poorer in reducing set time than K-FLEX® 850S. The open times, shown in FIG. 36, indicate similar performance between K-FLEX® 850S, X-615 and X-616, with poorer performance in the X-613 and X-614 samples. Depending on particular set and open time requirements and application, the X-600 series plasticizers may provide a viable alternative even though performing poorly in the set time and some of the open time evaluations.

[0206] Table 9, below, reflects data obtained for film clarity, Tg (5 C°/min), set time and open time for 5, 10 and 15% plasticizer levels, wet. Table 10 reflects the same data set for homopolymers adhesive formulations for 5, 10, 15 and 20% plasticizer levels, wet. No clarity data was obtained for X-616.

TABLE-US-00012 TABLE 9 Copolymer Film Clarity, Tg and Set/Open Times Film Film Tg Set Open Clarity Clarity (5 C./min) Time Time Plasticizer Wt. % 1-Day 7-Day (° C.) (s) (s) Blank 0 8 7 3.0 K-FLEX ® 5 9 8 −5.7 7.3 30 850S 10 9 8 −8.11 7.0 40 15 9 9 −14.7 5.0 45 X-613 5 9 8 −9.4 7.3 30 10 9 8 −13.64 7.0 35 15 9 9 −17.9 6.0 45 X-614 5 9 8 −7.5 6.3 30 10 9 8 −10.58 5.7 40 15 9 9 −22.8 5.7 45 X-615 5 9 8 −9.2 8.0 30 10 9 8 −14.92 6.3 40 15 9 9 −21.6 5.7 45 X-616 5 9 8 −9.6 7.7 30 10 9 8 −14.55 6.3 40 15 9 9 −22.6 5.7 45

TABLE-US-00013 TABLE 10 Homopolymer Film Clarity, Tg and Set/Open Times Film Film Tg Set Open Clarity Clarity (5 C./min) Time Time Plasticizer Wt. % 1-Day 7-Day (° C.) (s) (s) Blank 0 7 7 33.5 9.3 10 K-FLEX ® 5 8 8 18.2 7.0 15 850S 10 9 9 8.4 6.0 25 15 9 9 −1.4 5.7 35 20 9 9 −10.9 4.3 45 X-613 5 8 8 18.2 9.0 15 10 8 9 7.7 7.7 20 15 9 9 −5.1 6.7 30 20 9 9 −16.1 5.7 40 X-614 5 8 8 19.7 8.7 10 10 8 9 7.4 7.3 20 15 9 9 −1.2 6.7 30 20 9 9 −10.9 4.7 40 X-615 5 8 9 12.5 8.7 15 10 9 9 2 7.7 25 15 9 9 −11 7.3 40 20 10 9 −19.4 6.0 45 X-616 5 13.8 8.3 15 10 0.9 7.3 30 15 −10.8 6.7 40 20 −18.6 4.7 45

[0207] While the X-600 series plasticizers evaluated in this example did not have any particular aspect that stood out aside from Tg suppression, they were generally found to be compatible and to produce similar performance to the traditional diblend, particularly in the copolymer system. Therefore, it would be expected that any member of this series could serve as a plasticizer in a waterborne adhesive depending on the particular requirements and application.

[0208] In accordance with the patent statutes, the best mode and preferred embodiments have been set forth; the scope of the invention is not limited thereto, but rather by the scope of the attached claims.