Polymer compositions containing aliphatic esters as plasticisers

Abstract

Disclosed is the use of a composition of aliphatic esters having the following general formula: R.sub.1OC(O)R.sub.4C(O)[OR.sub.2OC(O)R.sub.5C(O)].sub.mOR.sub.3, in which: R.sub.1 is selected from one or more of the groups consisting of H, linear and branched saturated and unsaturated alkyl residues of the C.sub.1-C.sub.24 type, and polyol residues esterified with C.sub.1-C.sub.24 monocarboxylic acids; R.sub.2 comprises CH.sub.2C(CH.sub.3).sub.2CH.sub.2 and C.sub.2-C.sub.8 alkylene groups, and comprises at least 50% in moles of the said CH.sub.2C(CH.sub.3).sub.2CH.sub.2 groups; R.sub.3 is selected from one or more of the groups consisting of H, linear and branched saturated and unsaturated alkyl residues of the C.sub.1-C.sub.24 type, and polyol residues esterified with C.sub.1-C.sub.24 monocarboxylic acids; R.sub.4 and R.sub.5 comprise one or more C.sub.2-C.sub.22 alkylenes and comprise at least 50% in moles of C.sub.7 alkylenes; and m lies between 1 and 20, as plasticizers for polymer compositions, for example, vinyl polymers of the polyvinyl chloride (PVC) type, thermoplastic elastomers, and hydroxy acid polyesters, for example polyesters of lactic acid.

Claims

1. A polymer composition comprising at least one thermoplastic polymer, and at least one plasticizer comprising a composition of one or more aliphatic esters having general formula:
R.sub.1OC(O)R.sub.4C(O)[OR.sub.2OC(O)R.sub.5C(O)].sub.mOR.sub.3 in which: R.sub.1 is selected from one or more of the groups consisting of H, linear and branched saturated and unsaturated alkyl residues of the C.sub.1-C.sub.24 type, and polyol residues esterified with C.sub.1-C.sub.24 monocarboxylic acids; R.sub.2 comprises CH.sub.2C(CH.sub.3).sub.2CH.sub.2 and C.sub.2-C.sub.24 alkylene groups, and comprises at least 50% by moles of the said CH.sub.2C(CH.sub.3).sub.2CH.sub.2 groups; R.sub.3 is selected from one or more of the groups consisting of H, linear and branched saturated and unsaturated alkyl residues of the C.sub.1-C.sub.24 type, and polyol residues esterified with C.sub.1-C.sub.24 monocarboxylic acids; R.sub.4 and R.sub.5 comprise one or more C.sub.2-C.sub.22 alkylenes and comprise at least 50% by moles of C.sub.7 alkylenes; m lies between 1 and 20; wherein R.sub.1 is different from R.sub.3 if R.sub.1 is H; and wherein at least one of the R.sub.1 and/or R.sub.3 is present in an amount of 10% by moles, with respect to the total amount of R.sub.1 and/or R.sub.3, of polyol residues esterified with at least one C.sub.1-C.sub.24 monocarboxylic acid selected from the group of stearic acid, palmitic acid, 9-ketostearic acid, 10-ketostearic acid and mixtures thereof.

2. The polymer composition according to claim 1, in which R.sub.1 is H and R.sub.3 is different from R.sub.1.

3. The polymer composition according to claim 2, in which R.sub.4 and R.sub.5 are C.sub.7 alkylenes.

4. The polymer composition according to claim 2, comprising from 10 to 80% by weight of the said aliphatic esters.

5. The polymer composition according to claim 2, in which said one or more thermoplastic polymers are selected from chlorinated vinyl polymers, thermoplastic elastomers and hydroxy acid polyesters.

6. The polymer composition according to claim 2, in which R.sub.2 is the CH.sub.2C(CH.sub.3).sub.2CH.sub.2group.

7. The polymer composition according to claim 6, in which R.sub.4 and R.sub.5 are C.sub.7 alkylenes.

8. The polymer composition according to claim 7, comprising from 10 to 80% by weight of the said aliphatic esters.

9. The polymer composition according to claim 6, comprising from 10 to 80% by weight of the said aliphatic esters.

10. The polymer composition according to claim 1, in which R.sub.2 is the CH.sub.2C(CH.sub.3).sub.2CH.sub.2group.

11. The polymer composition according to claim 10, in which R.sub.4 and R.sub.5 are C.sub.7 alkylenes.

12. The polymer composition according to claim 10, comprising from 10 to 80% by weight of the said aliphatic esters.

13. The polymer composition according to claim 10, in which said one or more thermoplastic polymers are selected from chlorinated vinyl polymers, thermoplastic elastomers and hydroxy acid polyesters.

14. The polymer composition according to claim 1, in which R.sub.4 and R.sub.5 are C.sub.7 alkylenes.

15. The polymer composition according to claim 14, comprising from 10 to 80% by weight of the said aliphatic esters.

16. The polymer composition according to claim 14, in which said one or more thermoplastic polymers are selected from chlorinated vinyl polymers, thermoplastic elastomers and hydroxy acid polyesters.

17. The polymer composition according to claim 1, comprising from 10 to 80% by weight of the said aliphatic esters.

18. The polymer composition according to claim 17, in which said one or more thermoplastic polymers are selected from chlorinated vinyl polymers, thermoplastic elastomers and hydroxy acid polyesters.

19. The polymer composition according to claim 1, in which said one or more thermoplastic polymers are selected from chlorinated vinyl polymers, thermoplastic elastomers and hydroxy acid polyesters.

20. A method for plasticizing a thermoplastic polymer composition which comprises incorporating in the thermoplastic polymer composition an aliphatic ester having general formula:
R.sub.1OC(O)R.sub.4C(O)[OR.sub.2OC(O)R.sub.5C(O)].sub.mOR.sub.3 in which: R.sub.1 is selected from one or more of the groups consisting of H, linear and branched saturated and unsaturated alkyl residues of the C.sub.1-C.sub.24 type, and polyol residues esterified with C.sub.1-C.sub.24 monocarboxylic acids; R.sub.2 comprises CH.sub.2C(CH.sub.3).sub.2CH.sub.2 and C.sub.2-C.sub.24 alkylene groups, and comprises at least 50% by moles of the said CH.sub.2C(CH.sub.3).sub.2CH.sub.2groups; R.sub.3 is selected from one or more of the groups consisting of H, linear and branched saturated and unsaturated alkyl residues of the C.sub.1-C.sub.24 type, and polyol residues esterified with C.sub.1-C.sub.24 monocarboxylic acids; R.sub.4 and R.sub.5 comprise one or more C.sub.2-C.sub.22 alkylenes and comprise at least 50% by moles of C.sub.7 alkylenes; m lies between 1 and 20; wherein R.sub.1 is different from R.sub.3 if R.sub.1 is H; and wherein at least one of the R.sub.1 and/or R.sub.3 is present in an amount of 10% by moles, with respect to the total amount of R.sub.1 and/or R.sub.3, of polyol residues esterified with at least one C.sub.1-C.sub.24 monocarboxylic acid selected from the group of stearic acid, palmitic acid, 9-ketostearic acid, 10-ketostearic acid and mixtures thereof.

Description

EXAMPLES

Example 1

Preparation of Aliphatic Esters According to the Invention

(1) A mixture comprising butyl esters and a smaller quantity of linear aliphatic dicarboxylic and monocarboxylic acids obtained by evaporation during the synthesis of the complex oligomer structures described in Example 1 of WO 2012/085012 was used to prepare the aliphatic esters. 100 grams of this mixture having the following composition:

(2) TABLE-US-00001 % in moles monobutyl azelate 3.1 dibutyl suberate 2 dibutyl azelate 82.6 butyl palmitate 4.1 dibutyl undecandioate 1 butyl stearate 3.1 butyl ketostearate 4.1 (1:1 mixture of butyl 10-ketostearate and butyl 9-ketostearate)
were placed together with 19 g of neopentylglycol in a flask heated by an electrical jacket and fitted with a thermometer, a magnetic stirrer, a reflux distillation column and glass rings and a system for regulating reflux into the flask, a condenser and a flask for collection of the condensate. The system was heated with stirring at 100 C., and once complete dissolution of the neopentylglycol had been achieved, 0.0223 g of Tyzor TE were added. The system was then gradually heated to 250 C., distilling from the reaction medium via butanol and water. After the temperature of 250 C. had been reached, gradual vacuum was applied until 20 mbar was reached. On completion of the reaction a condensate comprising butanol and water was recovered from the condenser.

(3) The aliphatic esters obtained took the form of a clear yellow liquid and were analysed by HPLC-MS. For the analysis 2 mg of the mixture of esters were dissolved in 10 ml of acetonitrile and analysed under the following conditions:

(4) Column: Kinetex 2.6 m C8 100 1002.1 mm

(5) Eluents:

(6) (A)=50 mM CH.sub.3COONH.sub.4 with HCOOH pH=4; (B)=CH.sub.3CN;
Elution programme

(7) TABLE-US-00002 Time (minutes) A (% vol) B(% vol) 0 40 60 30 5 95 50 5 95 55 40 60
Flow (ml/min): 0.5
Injector volume (l): 10
Column T ( C.): 40

(8) Mass spectrometer conditions: ESI ionising source (positive ionisation), Sheath gas flow rate (a.u.) 20, Aux gas flow rate (a.u.) 0, Source Voltage (Kv): 4.5, Capillary Temperature ( C.): 275, Capillary Voltage (V): 28, Tube Lens Voltage (V): 80, Scan: Full scan 150-2000 and 350-3500 Da

(9) HPLC-MS characterisation of the said esters revealed the presence of a mixture of compounds having the following structure:
R.sub.1OC(O)R.sub.4C(O)[OR.sub.2OC(O)R.sub.4C(O)].sub.mOR.sub.3
with R.sub.1 and R.sub.3H, butyl, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.7C(O)(CH.sub.2).sub.8CH.sub.3, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.8C(O)(CH.sub.2).sub.7CH.sub.3, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.14CH.sub.3, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.16CH.sub.3; R.sub.4 and R.sub.5C.sub.6 and C.sub.7 and C.sub.9 alkylenes, m being between 1 and 10 (mean value=3).

(10) Examples of these esters are:
CH.sub.3(CH.sub.2).sub.3OC(O)(CH.sub.2).sub.7C(O)[OCH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.7C(O)].sub.3O(CH.sub.2).sub.3CH.sub.3
HOC(O)(CH.sub.2).sub.7C(O)[OCH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.7C(O)].sub.3O(CH.sub.2).sub.3CH.sub.3
HOC(O)(CH.sub.2).sub.7C(O)[OCH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.7C(O)].sub.4OCH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.7C(O)(CH.sub.2).sub.8CH.sub.3

Examples 2-4

(11) Three mixtures of butyl esters having the following compositions:

(12) TABLE-US-00003 Example 2 (% 3 (% 4 (% in moles) in moles) in moles) butyl pelargonate 0.00 2.00 6.09 monobuyl azelate 13.29 9.37 9.62 dibutyl suberate 1.21 0.89 1.19 dibutyl azelate 64.05 45.37 41.48 butyl palmitate 8.16 14.61 14.88 dibutyl undecandioate 1.21 0.86 0.81 butyl oleate 0.91 1.50 1.48 butyl stearate 5.74 12.09 11.38 butyl ketostearate 5.14 11.19 10.81 (1:1 mixture of butyl 10-ketostearate and butyl 9-ketostearate) butyl arachidate 0.00 0.49 0.72 butyl behenate 0.30 1.63 1.56
were used to prepare three aliphatic esters in the same preparation conditions of Example 1 using the following amounts of neopentylglycol

(13) TABLE-US-00004 Example 2 Example 3 Example 4 Mixture of butyl ester (g) 1000 1000 1000 Neopentylglycol (g) 242.2 253.3 182.8

(14) HPLC-MS characterisation of the said esters revealed the presence of a mixture of compounds having the same general structure of the esters according to Example 1 with R.sub.1 and R.sub.3H, butyl, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.7C(O)(CH.sub.2).sub.8CH.sub.3, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.8C(O)(CH.sub.2).sub.7CH.sub.3, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.14CH.sub.3, CH.sub.2C(CH.sub.3).sub.2CH.sub.2OC(O)(CH.sub.2).sub.16CH.sub.3; R.sub.4 and R.sub.5C.sub.6 and C.sub.7 and C.sub.9 alkylenes, m being between 1 and 10 (mean value=3 for Examples 2 and 3, =2 for Example 4).

(15) Table 1 herebelow reports the amount of R.sub.1 and/or R.sub.3 groups of the esters according to Examples 1-4 comprising polyols residues esterified with at least one acid selected from stearic acid, palmitic acid, 9-ketostearic acid, 10-ketostearic acid and mixtures thereof, as determined according to the HPLC-MS analysis as above described in the present application.

(16) TABLE-US-00005 TABLE 1 % in moles of R.sub.1 and/or R.sub.3 groups comprising polyols % in moles of R.sub.1 and/or R.sub.3 residues esterified with at groups comprising polyols least one acid selected from residues esterified with at stearic acid, palmitic acid, least one acid selected from 9-ketostearic acid, 9-ketostearic acid, 10-ketostearic acid 10-ketostearic acid Es. 1 25.61 9.32 Es. 2 54.28 19.67 Es. 3 87.58 41.24 Es. 4 65.01 29.08

Examples 5 and 12

Use as Plasticizers for Polyvinyl Chloride

(17) The plasticising properties of the aliphatic esters according to the invention were compared with those of a conventional plasticiser, diisononyl phthalate (DINP, marketed by Polynt under the brand name DIPLAST NS) and ester of trimellitic acid with a blend of n-octanol and n-decanol (marketed by Polynt under the brand name DIPLAST TM 8-10/ST). Identical polymer compositions based on a grade of commercially available polyvinyl chloride (NORVINYL 7102 PVC, marketed by Ineos) which differed only in the type of plasticiser used were prepared for the purpose. The compositions are shown in Table 2.

(18) TABLE-US-00006 TABLE 2 Quantification by weight of the polymer compositions prepared according to Examples 5-12 Example 6 Example 11 Example 12 Example 5 comparison Example 7 Example 8 Example 9 Example 10 comparison comparison (parts by (parts by (parts by (parts by (parts by (parts by (parts by (parts by Material weight) weight) weight) weight) weight) weight) weight) weight) PVC .sup.1 100 100 100 100 100 100 100 100 Plasticiser .sup.1 50 50 Plasticiser .sup.2 50 Plasticiser .sup.3 50 Plasticiser .sup.4 50 Plasticiser .sup.5 50 50 Plasticiser .sup.6 50 Stabiliser .sup.1 1 1 Stabiliser .sup.2 1 1 Stabiliser .sup.3 8 8 8 8 8 8 PVC .sup.1 = PCV K70 (PVC NORVINYL 7102); Plasticiser .sup.1 = aliphatic ester prepared according to Example 1; Plasticiser .sup.2 = aliphatic ester prepared according to Example 2; Plasticiser .sup.3 = aliphatic ester prepared according to Example 3; Plasticiser .sup.4 = aliphatic ester prepared according to Example 4; Plasticiser .sup.5 - diisononyl phthalate (DINP); Plasticiser .sup.6 = ester of trimellitic acid with a blend of n-octanol and n-decanol (DIPLAST TM 8-10/ST); Stabiliser .sup.1 = calcium stearate; Stabiliser .sup.2 = zinc stearate; Stabiliser .sup.3 = Calcium/Zinc stabilizer (Bareopan MC 8890 KA/S).

(19) The polymer compositions were prepared in a HAAKE RHEOMIX 600 mixer according to compound preparation procedure reported in standard ASTM D2538: the individual components were weighed, homogenised by manual mixing and subsequently loaded into the mixer chamber. The following conditions were used for processing: Temperature=150 C. (Examples 5 and 6comparison) and 170 C. (Examples 7, 8, 9, 10, 11comparison, 12comparison); 40 r.p.m.; Mixing time: 7 minutes.

(20) The processing of the polymer compositions mixtures was comparable.

(21) Sheets of thickness 0.25 mm, 1.5 mm and 3.0 mm were compression moulded for each polymer compositions so prepared. During moulding the samples were moulded at 5000 psi and T=150 C. for 6 minutes (Example 5 and 6) and at 5000 psi and T=170 C. for 6 minutes (Example 7, 8, 9, 10, 11comparison, 12comparison). The compression moulded sheets were left to equilibrate for 24 hours at 23 C.1 C. and 50%5% RH.

(22) The polymer compositions were then compression moulded 5000 psi and T=150 C. for 6 minutes (Example 5 and 6) and 5000 psi and T=170 C. for 6 minutes (Example 7, 8, 9, 10, 11comparison, 12comparison)) obtaining sheets of different thickness for each (0.25 mm, 1.5 mm and 3.0 mm). The compression moulded sheets were allowed to equilibrate for 24 hours at 23 C.1 C. and 50%5% RH and were characterised by analysing their tensile properties, their Shore A hardness and their resistance to extraction in different solvents as well as their properties as a function of temperature.

(23) Determination of Tensile Properties

(24) Tensile properties were determined in accordance with Standard ASTM D412, using a rate of extension v=500 mm/min. The test samples were obtained by punching out the sheets of thickness 1.5 mm. A cutting die according to standard ASTM D 412 was used to prepare the samples. The tensile strength (.sub.b), the maximum load (.sub.max), the elongation corresponding to the tensile strength (.sub.b), the elongation corresponding to the maximum load (@.sub.max) and the Elastic Modulus for an elongation of 100% (E.sub.100%), 200% (E.sub.200%) and 300% (E.sub.300%) were measured for each mixture. The same properties and the weight loss were determined also on the samples after ageing in a ventilated oven maintained at 140 C. for 7 days. Before testing, aged samples were allowed to equilibrate for 24 hours at 23 C.1 C. and 50%5% RH.

(25) Determination of Shore A Hardness

(26) Shore A hardness was determined according to standard ASTM D2240. The samples were obtained by obtaining 3.0 cm3.0 cm samples from the compression moulded sheets of thickness 3.0 mm obtained by compression moulding. The samples so obtained were stacked to achieve a final thickness of at least 6.0 mm in accordance with the procedure specified in standard ASTM D2240. The Shore A hardness value has been recorded after 15 seconds from the beginning of the measure.

(27) Resistance to Extraction in Different Solvents

(28) The resistance of the plasticizers to extraction in different solvents was evaluated using the procedure described in standard ASTM D1239. The samples were obtained by cutting samples of dimensions 5.0 cm5.0 cm from the compression moulded sheets of thickness 0.25 mm. The following solvents were used for the extraction tests: Soapy water: distilled water containing 1.0% by weight of Marseille soap. The soap had been previously dehydrated by leaving it in a ventilated stove at 105 C. for 60 minutes. The extraction tests were performed at 40 C. over 24 hours. Oil: sunflower oil having a high oleic acid content (Agripur AP 80). The extraction tests were performed at 40 C. over 24 hours. n-octane: the extraction tests were performed at 23 C. over 24 hours.

(29) On completion of the tests the samples were washed to remove any traces of possible solvents, dried with a sheet of paper and allowed to equilibrate at 20 C. for 24 hours.

(30) DMTA Analysis

(31) The DMTA analysis were performed using a rotational rheometer TA instruments Ares G2. The measurements were made by using the torsion geometry mode with a rectangular sample in a temperature window of from 80 C. to 50 C. with a temperature rate of 3 C./minute. For the analysis a frequency of oscillation 1 Hz and 0.1% of deformation was used. A second set of samples was aged in a ventilated oven maintained at 140 C. for 7 days and the DMTA properties were determined also on these samples. Before testing, aged samples were allowed to equilibrate for 24 hours at 23 C.1 C. and 50%5% RH.

(32) As will be seen from the data shown in Table 3a, the tensile properties and Shore A hardness of the PVC mixtures plasticised with aliphatic esters according to the invention (Example 5, 7, 8, 9, 10) are similar to those of the comparison mixtures plasticised using DINP (Example 6 and 11comparison) and using DIPLAST TM 8-10/ST Example 12comparison).

(33) TABLE-US-00007 TABLE 3a Tensile and Shore A hardness properties of the mixtures .sub.MAX at MAX .sub.b .sub.b E.sub.100% E.sub.200% E.sub.300% Shore (MPa) (%) (MPa) (%) (MPa) (MPa) (%) A Example 5 18.8 365.7 18.8 365.7 8.2 6.5 5.6 76 Example 6 - 19.1 348.0 19.1 348.0 10.2 7.4 6.0 82 comparison Example 7 19.26 313.54 19.26 313.54 10.1 7.56 6.35 77 Example 8 20.60 352.43 20.60 352.43 11.78 8.08 6.40 80 Example 9 21.10 361.83 21.10 361.83 12.70 8.17 6.42 84 Example 10 16.50 287.34 16.50 287.34 9.83 6.94 5.60 78 Example 11 - 20.20 330.15 20.20 330.15 12.32 8.18 6.48 82 comparison Example 12 - 21.3 245.5 21.3 245.5 14.3 8.75 6.70 90 comparison

(34) As can be seen from the data on Table 3b, the samples containing the esters according to the present invention retain relevant mechanical properties after ageing, similarly to DIPLAST TM 8-10/ST. The polymer composition plasticized with DINP, instead, has shown a remarkable reduction of the mechanical properties.

(35) TABLE-US-00008 TABLE 3b Tensile properties of the mixtures after ageing in a ventilated oven at 140 C. for 7 days .sub.MAX .sub.at MAX .sub.b .sub.b E.sub.100% E.sub.200% E.sub.300% Weight (MPa) (%) (MPa) (%) (MPa) (MPa) (%) loss (%) Example 7 21.45 287.83 21.45 287.83 17.58 10.03 7.20 8.55 Example 8 21.05 334.55 21.05 334.55 15.93 9.35 6.85 4.92 Example 9 21.48 354.93 21.48 354.93 15.15 9.15 6.73 4.22 Example 10 20.80 186.27 20.80 186.27 19.47 10.10 n.d.* 11.04 Example 11 - 63.40 1.80 63.40 1.80 n.d.* n.d.* n.d.* 23.37 comparison Example 12 - 19.15 316.43 19.15 316.43 14.08 8.53 6.28 0.99 comparison *n.d. = not detectable

(36) As for the tests of resistance to extraction of the plasticizers, Table 4 shows the % loss in weight of the test pieces subjected to the tests described above.

(37) TABLE-US-00009 TABLE 4 Resistance to extraction in different solvents Soapy water Oil n-octane Example 5 5.3 8.1 10.40 Example 6 - comparison 1.2 11.1 23.92 Example 7 5.82 9.55 12.09 Example 8 1.91 6.52 9.91 Example 9 2.05 8.82 12.83 Example 10 8.30 15.15 ,18.99 Example 11 - comparison 1.06 13.28 22.08 Example 12 - comparison 0.5 12.9 24.5

(38) Considering both the process of preparation and the mechanical properties and resistance to extraction by solvents properties of the mixtures obtained, the aliphatic esters according to the invention appear to be wholly equivalent to conventional plasticizers.

(39) With regard to the DMTA analysis, the herebelow tables show the values of G @ 25 C., G @ 25 C., Onset G, Max G and Max Tan () for the polymer compositions of Examples 7-12 as such (Table 5a) and after 7 days of ageing in a ventilated oven maintained at 140 C. (Table 5b).

(40) TABLE-US-00010 TABLE 5a Ex. 11 - Ex. 12 - Ex. 7 Ex. 8 Ex. 9 Ex. 10 comparison comparison G @ 25 C. (MPa) 11 25 38 23 27 72 G @ 25 C. (MPa) 760 1300 950 710 812 650 Max G ( C.) 27 18 19 31 29 33 Max Tan () ( C.) 12 21 27 18 22 46

(41) TABLE-US-00011 TABLE 5b Ex. 11 - Ex. 12 - Ex. 7 Ex. 8 Ex. 9 Ex. 10 comparison comparison G @ 25 C. (MPa) 83 68 69 173 1210 75 G @ 25 C. (MPa) 1300 1600 1300 1400 1390 730 Max G ( C.) 0 3 9 6 50 31 Max Tan () ( C.) 34 31 33 45 50 50

Examples 13Comparison, 14, 15 and 16Comparison

(42) TABLE-US-00012 Example 13 - Example 16 - comparison Example Example comparison (parts by 14 (parts 15 (parts (parts by Material weight) by weight) by weight) weight) PVC .sup.1 100 100 100 100 Plasticiser .sup.6 50 . Plasticiser .sup.2 50 . Plasticiser .sup.3 50 Plasticiser .sup.5 50 Filler .sup.1 30 30 30 30 Oil .sup.1 5 5 5 5 Stabilizer .sup.3 8 8 8 8 Stabilizer .sup.4 1 1 1 1 PVC .sup.1 = PCV K70 (PVC NORVINYL 7102); Plasticiser .sup.2 = aliphatic ester prepared according to Example 2; Plasticiser .sup.3 = aliphatic ester prepared according to Example 3; Plasticiser .sup.5 - diisononyl phthalate (DINP); Plasticiser .sup.6 = ester of trimellitic acid with a blend of n-octanol and n-decanol (DIPLAST TM 8-10/ST); Filler .sup.1 = CaCO.sub.3; Oil .sup.1 = epoxidised soybean oil; Stabiliser .sup.3 = Calcium/Zinc stabilizer (Bareopan MC 8890 KA/S); Stabiliser .sup.4 = Octadecyl-3-(3,5-di-tert.butyl-4-hydroxyphenyl)-propionate (Irganox 1076, marketed by BASF).

(43) The polymer compositions were prepared in a HAAKE RHEOMIX 600 mixer according to standard ASTM D2538: the individual components were weighed, homogenised by manual mixing and subsequently loaded into the mixer chamber. The following conditions were used for processing: Temperature=and 170 C.; 40 r.p.m.; Mixing time: 7 minutes.

(44) The processing of the polymer compositions mixtures was comparable.

(45) Sheets of thickness 1.5 mm were compression moulded for each polymer compositions so prepared. During moulding the samples were moulded at 5000 psi and T=170 C. for 6 minutes. The compression moulded sheets were left to equilibrate for 24 hours at 23 C.1 C. and 50%5% RH.

(46) The polymer compositions were then compression moulded (T=170 C. for 6 minutes) obtaining sheets of 1.5 mm thickness for each polymer compositions prepared. The compression moulded sheets were allowed to equilibrate for 24 hours at 23 C. and 55% RH and were characterised by analysing their tensile properties according to the method above disclosed (Tables 6a and 6b).

(47) TABLE-US-00013 TABLE 6a Tensile properties of the polymer compositions as such .sub.MAX at MAX .sub.b .sub.b (MPa) (%) (MPa) (%) Example 13 - 15.95 269.70 15.95 269.70 comparison Example 14 15.83 309.42 15.83 309.42 Example 15 15.14 260.01 15.14 260.01 Example 16 - 17.08 326.58 17.08 326.58 comparison

(48) TABLE-US-00014 TABLE 6b Tensile properties of the polymer compositions after 7 days of ageing in a ventilated oven maintained at 140 C. Weight .sub.MAX at MAX .sub.b .sub.b loss (MPa) (%) (MPa) (%) (%) Example 13 - 14.84 257.40 14.84 257.40 0.32 comparison Example 14 15.66 250.97 15.66 250.97 3.52 Example 15 15.57 248.06 15.57 248.06 2.65 Example 16 - 38.00 2.20 38.00 2.20 22.28 comparison