Polymeric materials

Abstract

Additives such as colourants may be incorporated into polymeric materials such as polyesters, such as in polyester fibre production, by use of a liquid formulation comprising colourant and a vehicle. The vehicle may comprise a functionalised pentaerythritol, trimethylolpropane or trimellitate. The liquid formulation is suitably contacted with the polymeric material in a melt processing apparatus.

Claims

1. A liquid formulation for addition to a polymeric material, said liquid formulation comprising an additive and a vehicle wherein said vehicle is pentaerythritol tetraisostearate, wherein said additive comprises a colorant, wherein said liquid formulation includes at least 20 wt % of vehicle and 80 wt % or less of vehicle, wherein the total a mount of additives in said formulation is in the range 20-60 wt %.

2. A liquid formulation according to claim 1, wherein said liquid formulation includes less than 5 wt % of a dispersant.

3. A liquid formulation according to claim 1, wherein said colorant is a dye.

4. A liquid formulation according to claim 1, wherein said colorant is a dye, said vehicle is pentaerythritol tetraisostearate, the total amount of additives in said formulation is in the range 20-60 wt %, said liquid formulation includes at least 20 wt % of vehicle and 80 wt % or less of vehicle, and said liquid formulation includes less than 5 wt % of a dispersant.

5. An assembly comprising: (a) an extruder for extruding polymeric material; (b) a receptacle containing a liquid formulation as described in claim 1; (c) injection means operatively connected to the receptacle for injecting liquid formulation extracted from the receptacle into the polymeric material in or downstream of the extruder; (d) mixing means for mixing liquid formulation and polymeric material; and (e) spinning means downstream of the extruder for receiving the polymeric material which has been contacted with said liquid formulation and spinning the polymeric material to produce fibre.

6. An assembly according to claim 1, wherein said extruder contains a polymeric material which is a polyester.

7. An assembly according to claim 6, wherein said colorant is a dye, said vehicle is pentaerythritol tetraisostearate, the total amount of additives in said formulation is in the range 20-60 wt %, said liquid formulation includes at least 20 wt % of vehicle and 80 wt % or less of vehicle, and said liquid formulation includes less than 5 wt % of a dispersant.

8. A liquid formulation for addition to a polymeric material, said liquid formulation comprising an additive and a vehicle wherein said vehicle is pentaerythritol tetraisostearate, wherein said additive comprises a colorant, wherein said liquid formulation includes at least 20 wt % of vehicle and 80 wt % or less of vehicle, wherein the total amount of additives in said formulation is in the range 5-80 wt %.

Description

BRIEF DESCRIPTION OF THE DRAWING:

(1) FIG. 1 is a schematic representation of a pilot fibre line.

(2) Specific embodiments of the invention will now be described, by way of example with reference to FIG. 1.

(3) The following materials are referred to hereinafter:

(4) Pentaerythritol ethoxylate exSigma-Aldrich CAS No. 30599-15-6

(5) Trimethylolpropane ethoxylate exSigma-Aldrich Cas No. 50586-59-9

(6) Lauric acid exSigma-Aldrich Cas No. 143-07-7

(7) Decanoic acid exSigma-Aldrich Cas No. 334-48-5

(8) N,N-Dicyclohexylcarbodiimide exSigma-Aldrich Cas No. 538-75-0

(9) 4-Dimethylaminopyridine exSigma-Aldrich Cas No. 1122-58-3

(10) Dichloromethane exSigma-Aldrich Cas No. 75-09-2

(11) Magnesium sulphate exSigma-Aldrich Cas No. 7487-88-9

(12) PTIS—pentaerythritol tetraisostearate sold as CRODAMOL™ PTIS by Croda.

(13) PTO—pentaerythritol tetraioleate sold as PS2057™ by Esterchem Ltd.

(14) PTC—pentaerythritol tetracaprylate/caprate sold as Crodamol PTC [LQ];

(15) PTL-EO—pentaerythritol tetralaurate ethoxylate synthesized in laboratory to 90% purity by Colormatrix.

(16) TTIS—trimethylolpropane triisostearate sold as Crodamol TTIS [LQ] by Croda.

(17) TTC-EO—trimethylolpropane tricaprate ethoxylate synthesized in laboratory to 89% purity by Colormatrix.

(18) TDTM—tri-n-tridecyl trimellitate sold as Pelemol™ TDTM by Phoenix Chemical Inc.

(19) TOTM—trioctyltrimellitate sold as DiPlast TM8 by Polynt SA.

(20) Liquid carriers referred to herein may be commercially available and/or may be made in processes the same as/or similar to the processes of Examples A and B below.

(21) Table 1 summarises features of the aforementioned liquid carriers.

(22) TABLE-US-00001 TABLE 1 Ester Alkyl Number of ester Calculated Material chain length main chains molecular mass PTIS 18 4 1202 PTO 18 4 1194 PTC 8/10 4 685 PTL-EO 12 4 1525 TTIS 18 3 934 TTC-EO 10 3 912 TDTM 13 3 757 TOTM  8 3 547

(23) In general terms, apparatus for use in the method may be as described in FIG. 1. Injection apparatus 4, for example a cavity transfer mixer, may be used to inject liquid containing vehicle(s) and additive(s) into a PET melt at position 2. Die head pressure may be assessed at position 3. The mixture is spun via spinning head 6.

(24) In the following, Example 1 describes a thermogravimetric analysis (TGA) of vehicles which is relevant to whether or not the vehicle may disadvantageously fume at a die exit in use. Examples 2 and 3 describe how the intrinsic viscosity and fibre tenacity of spun samples may be assessed. Examples 4 to 12 describe formulations and/or tests on a range of formulations to illustrate advantages of preferred vehicles. Examples 13 and 14 describe formulations used in fibre formation.

EXAMPLE 1

Determination of TGA Weight Retention

(25) Using a TA Instruments TGA Q500 the TGA weight retention of the example liquid carriers was determined by placing 10 mg of a selected carrier in a TGA sample pan and recording the weight loss on heating from 40° C. to 295° C. at 20° C./min and then holding the sample at 295° C. for 30 minutes. After this heating cycle the % weight retention was recorded.

EXAMPLE 2

Determination of Intrinsic Viscosity (IV)

(26) The intrinsic viscosity of PET fibre samples was determined using ASTM D4603 at 30° C. (concentration of 0.5 wt/v; solvent 60/40 phenol/tetrachloroethane).

EXAMPLE 3

Determination of Fibre Tenacity

(27) Using an Instron 3365 the tenacity of the fibre sample was determined at 20° C. and an extension rate of 250 mm/min (ASTM D885).

COMPARATIVE EXAMPLE 4

Processing in the Absence of Vehicle and Testing

(28) A sample of medium orientated (MO) polyethylene terephthalate (PET) fibre was produced by melt extruding a sample of PET (Equipolymers C93), that had been dried for 4 hrs at 170° C. through a 30 mm extruder (L/D ratio of 24/1) fitted with a cavity transfer mixer (CTM) and a 72 hole (hole diameter 0.4 mm) spin pack at 285° C. The extruded fibre was drawn from the spinneret at 2500 m/min. Table 2 records the tensile properties of the fibre measured in accordance with Example 3 and the IV of the fibre measured in accordance with Example 2.

COMPARATIVE EXAMPLE 5

Processing in the Presence of Comparative Vehicle and Testing

(29) The fibre extrusion process in example 4 was used to produce a sample of MO PET fibre containing 1.5% PTC which was fully dispersed into the molten polymer by injection into the CTM (mixer speed 45 rpm). The extruded fibre was drawn from the spinneret at 2500 m/min. During extrusion fumes and an unpleasant odour were detected at the die plate. Table 2 records the tensile properties of the fibre measured in accordance with Example 3 and the IV of the fibre measured in accordance with Example 2.

EXAMPLES 6, 7 and 8

Processing in the Presence of Vehicles and Testing

(30) The process of Example 5 was repeated to produce fibres using 1.5% PTO, 1.5% PTIS, and 1.5% TDTM, respectively. Table 2 records the tensile properties of the fibre measured in accordance with Example 3 and the IV of the fibre measured in accordance with Example 2.

COMPARATIVE EXAMPLE 9

Processing in the Presence of Comparative Vehicle and Testing

(31) The process of Example 5 was repeated to produce fibre sample containing 1.5% TOTM.

(32) During extrusion a considerable level of fumes were observed at the die plate. Table 2 records the tensile properties of the fibre measured in accordance with Example 3 and the IV of the fibre measured in accordance with Example 2.

EXAMPLES 10 to 12

Processing in the Presence of Vehicles and Testing

(33) The process of Example 5 was repeated to produce fibres using 1.5% PTL-EO, 1.5% TTIS and 1.5% TTC-EO respectively. Table 2 records the tensile properties of the fibre measured in accordance with Example 3 and the IV of the fibre measured in accordance with Example 2.

(34) TABLE-US-00002 TABLE 2 Flash TGA point weight Die Intrinsic Fibre Fuming Carrier COC retention pressure viscosity tenacity observation at Example system (° C.) (wt %) (bar) (dL/g) (cN/dtex) die exit Comparative None — — 75 0.657 2.41 None Example 4 Comparative 1.5% PTC ≥270 73.58 46 0.601 1.93 Fumes & odour Example 5 Example 6 1.5% PTO ≥285 95.61 59 0.633 2.15 No Fumes Example 7 1.5% PTIS ≥300 97.60 59 0.632 2.22 No Fumes Example 8 1.5% ≥275 87.56 58 0.623 2.14 Negligible TDTM Fumes Comparative 1.5% ≥250 58.15 55 0.616 2.06 Considerable Example 9 TOTM fuming Example 10 1.5% ≥285 88.30 57 0.618 2.10 Negligible PTL-EO Fumes Example 11 1.5% ≥300 97.23 60 0.628 2.26 No Fumes TTIS Example 12 1.5% ≥285 87.50 58 0.619 2.16 Negligible TTC-EO Fumes

(35) Table 2 also details the flash point for each vehicle, determined in accordance with ASTM D92 (Cleveland Open Cup (COC) method), this being relevant to the thermal stability of the vehicle, in use. Additionally, the table details the die pressure head drop of the polymer melt measured at point 3 in FIG. 1. As the die head pressure is reduced it starts to affect the properties of the spun fibre and increase the rate of filament breaks.

(36) From the results in Table 2, the following should be noted:

(37) (a) Preferred carriers exhibit no or negligible fuming at the die exit whereas comparative examples 4, 5 and 9 disadvantageously exhibit considerable fuming and/or odour;

(38) (b) Preferred carriers have a flash point of 275° C.;

(39) (c) Preferred carriers exhibit higher TGA weight retention than the comparative examples;

(40) (d) Use of preferred carries results in higher die pressures than the comparative examples;

(41) (e) Use of preferred carries results in higher polymer IV which is closer to polymer IV when no carrier is used;

(42) (f) Use of preferred carriers leads to high fibre tenacity.

EXAMPLE 13

Preparation of Fibre Filaments Incorporating White Pigment

(43) A dispersion of 700 g of titanium dioxide (Hombitan LC-S), 128.9 g of TDTM, 128.8 g of PTIS 40.3 g Solsperse 3000 pigment dispersant from Lubrizol, 1 g Irganox 1010 (anti-oxidant) and 1 g Doverphos S9228T (anti-oxidant) was mixed using a high shear disperser for 2 minutes until all the components were fully dispersed. The dispersion had a Brookfield viscosity at 20° C. of 10,100 cP (spindle 7, 20 rpm). 35 g of the dispersion was mixed with 1000 g dry PET pellets (Equipolymers C93) and extruded into fibre on 30 mm extruder (LID ratio of 24/1) fitted with a 72 hole (hole diameter 0.4 mm) spin pack at 285° C. The extruder fibre was drawn from the spinneret at 2800 m/min.

(44) During extrusion of the fibre no fuming was observed at the die plate. The tenacity of the fibre produced was 2.18 cN/dtex; measured in accordance with Example 3. A representative sample of the fibre was examined by optical microscopy which shows that a very good dispersion of the titanium dioxide pigment throughout the fibre filaments.

EXAMPLE 14

Preparation of Fibre Filaments Incorporating Black Pigment

(45) A dispersion of 300 g of carbon black (Monarch 430), 4180 g PTIS, 60 g TOTM, 160 g Tegomer DA100N, 60 g Solplus (TM)K240 (pigment dispersant), 1 g Irganox 1010 (anti-oxidant) and 1 g Doverphos S9228T (anti-oxidant) were mixed and milled using a Eiger bead mill (1 mm diameter glass beads) for 45 mins until all the components were fully dispersed and the particle size of the dispersion (determined by optical microscopy) was less than 5 μm. The milled dispersion had a Brookfield viscosity at 20° C. of 15,100 cP (spindle 7, 20 rpm). The fibre extrusion process in example 4 was used to produce a sample of MO PET fibre containing 2% of this carbon black dispersion which was fully dispersed into the molten polymer by injection into the CTM (mixer speed 80 rpm). The extruder fibre was drawn from the spinneret at 2800 m/min.

(46) During extrusion of the fibre no fuming was observed at the die plate. The tenacity of the fibre produced was 2.015 cN/dtex; measured in accordance with Example 3. A representative sample of the fibre was examined by optical microscopy which shows that a very good dispersion of the carbon black pigment throughout the fibre filaments.

(47) Thus, it is clear from the above that preferred vehicle can be used to advantageously produce fibre filaments incorporating pigments (or other additives).

(48) The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.