Method for the manufacture of poly(aliphatic ester-carbonate) compositions and articles thereof
A process of preparing a compounded hydrostable poly(aliphatic ester-carbonate) includes providing a hydrostable poly(aliphatic ester-carbonate), compounding in an extruder the hydrostable poly(aliphatic ester-carbonate) and 0.05 wt % to 0.60 wt % of a multifunctional epoxide compounding stabilizer, based on the total weight of the compounded hydrostable poly(aliphatic ester-carbonate), under vacuum of 17000 to 85000 Pascals, and a torque of 30% to 75%, to provide the compounded hydrostable poly(aliphatic ester-carbonate). After compounding, at least one of the following apply: the inter-sample variability in molecular weight is less than 5%, wherein inter-sample variability is determined by comparing five 100 mil chips of the compounded hydrostable poly(aliphatic ester-carbonate); the % weight average molecular weight (MW) difference is less than 5% after hydroaging at 85° C. and 85% humidity; or the compounded poly(aliphatic ester-carbonate) has less than 75 ppm of unreacted —COOH end groups measured by 31 P NMR.
1. A process of preparing a compounded hydrostable poly(aliphatic ester-carbonate), the process comprising
providing a hydrostable poly(aliphatic ester-carbonate), wherein the hydrostable poly(aliphatic ester-carbonate) has a percent (%)molecular weight difference of less than 30%, after hydroaging a molded sample for 4 weeks at 85° C. and 85% humidity, and
compounding in an extruder the hydrostable poly(aliphatic ester-carbonate) and 0.05 wt % to 0.60 wt % of a multifunctional epoxide compounding stabilizer, based on the total weight of the compounded hydrostable poly(aliphatic ester-carbonate), under a vacuum of 17,000 to 85,000 Pascals, and a torque of 30% to 65% to provide the compounded hydrostable poly(aliphatic ester-carbonate),
wherein, after compounding, at least one of the following apply:
an inter-sample variability in molecular weight is less than 5%, wherein the inter-sample variability is determined by comparing the weight average molecular weight of five 2.54 mm molded chips of the compounded hydrostable poly(aliphatic ester-carbonate),
a percent (%) molecular weight difference is less than 18% after hydroaging a molded sample for 4 weeks at 85° C. and 85% humidity, or
the compounded poly(aliphatic ester-carbonate) has less than 140 ppm by weight of unreacted —COOH end groups measured by 31 P NMR, and
wherein the % molecular weight difference is determined according to equation (1)
%
molecular
weight
difference
=
MW
(
sample
at
week
0
)
-
MW
(
sample
at
week
X
)
MW
(
sample
at
week
0
)
⨯
(
100
)
(
1
)
wherein MW is the weight average molecular weight and X is the number of weeks.
2. The process of claim 1 , wherein the multifunctional epoxide compounding stabilizer comprises
a diglycidyl ester or a polyglycidyl ester of a dicarboxylic acid or a polycarboxylic acid;
a diglycidyl ether or polyglycidyl ether of a diol or a polyol;
a copolymer of styrene and a glycidyl(meth)acrylate; or
a combination thereof.
3. The process of claim 2 , wherein the multifunctional epoxide compounding stabilizer comprises a copolymer of styrene and a glycidyl(meth)acrylate.
4. The process of claim 1 , wherein the vacuum is 64,300 to 71,200 Pascals.
5. The process of claim 1 , wherein the hydrostable poly(aliphatic ester-carbonate) has a weight average molecular weight of 10,000 to 50,000 Dalton, as measured by gel permeation chromatography, calibrated using polystyrene standards, and corrected for the molecular weight of polycarbonate.
6. The process of claim 1 , wherein the hydrostable poly(aliphatic ester-carbonate) comprises 5 to 12 mole percent of units derived from a C 6-20 aliphatic dicarboxylic acid.
7. The process of claim 1 , wherein the C 6-20 aliphatic dicarboxylic acid is adipic acid, sebacic acid, or dodecanoic acid.
8. The process of claim 1 , wherein the hydrostable poly(aliphatic ester-carbonate) comprises units derived from 4,4′-dihydroxybiphenyl, 2,2-bis(4-hydroxyphenyl) propane, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)diphenylmethane, bis(4-hydroxyphenyl)-1-naphthylmethane, 1,2-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane, 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane, or 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane.
9. A method of improving hydrostability of a compounded hydrostable poly(aliphatic ester-carbonate), comprising
providing a hydrostable poly(aliphatic ester-carbonate), wherein the hydrostable poly(aliphatic ester-carbonate) has a percent (%)molecular weight difference of less than 30% after hydroaging a molded sample for 4 weeks at 85° C. and 85% humidity, and
compounding in an extruder the hydrostable poly(aliphatic ester-carbonate) and 0.05 wt % to 0.60 wt % of a multifunctional epoxide compounding stabilizer, based on the total weight of the compounded hydrostable poly(aliphatic ester-carbonate), under vacuum of 17,000 to 85,000 Pascals, and a torque of 30% to 75%, to provide the compounded hydrostable poly(aliphatic ester-carbonate),
wherein the % molecular weight difference is determined according to equation
%
molecular
weight
difference
=
MW
(
sample
at
week
0
)
-
MW
(
sample
at
week
X
)
MW
(
sample
at
week
0
)
⨯
(
100
)
(
1
)
wherein MW is the weight average molecular weight and X is the number of weeks.
10. The method of claim 9 , wherein, after compounding, the compounded hydrostable poly(aliphatic ester-carbonate) has at least one of the following
an inter-sample variability in molecular weight that is less than 5%, wherein the inter-sample variability is determined by comparing the weight average molecular weight of five 2.54 mm molded chips of the compounded hydrostable poly(aliphatic ester-carbonate),
the percent (%)molecular weight difference is less than 18% after hydroaging a molded sample for 4 weeks at 85° C. and 85% humidity, or
the compounded poly(aliphatic ester-carbonate) has less than 140 ppm by weight of unreacted —COOH end groups after hydroaging for 4 weeks at 85° C. and 85% humidity, as measured by 31 P NMR.
11. The process of claim 1 , wherein the percent (%) molecular weight difference is at least 40% less than a percent (%) molecular weight difference, after hydroaging molded samples for 4 weeks at 85° C. and 85% humidity, of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer at the same torque and under a vacuum that is less than 17,000 Pascals.
12. The process of claim 1 , wherein the percent (%) molecular weight difference is at least 30% less than a percent (%) molecular weight difference, after hydroaging molded samples for 4 weeks at 85° C. and 85% humidity, of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer under the same vacuum and at a torque that is greater than 65%.
13. The process of claim 1 , wherein the percent (%) molecular weight difference is at least 40% less than a percent (%) molecular weight difference, after hydroaging molded samples for 4 weeks at 85° C. and 85% humidity, of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer under a vacuum that is less than 17,000 Pascals and at a torque that is greater than 65%.
14. The process of claim 1 , wherein the amount of unreacted —COOH end groups is at least 40% less than an amount of unreacted —COOH end groups, after hydroaging molded samples for 4 weeks at 85° C. and 85% humidity, of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer at the same torque and under a vacuum that is less than 17,000 Pascals.
15. The process of claim 1 , wherein the amount of unreacted —COOH end groups is at least 40% less than an amount of unreacted —COOH end groups, after hydroaging molded samples for 4 weeks at 85° C. and 85% humidity, of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer under the same vacuum and at a torque that is greater than 65%.
16. The process of claim 1 , wherein the amount of unreacted —COOH end groups is at least 60% less than an amount of unreacted —COOH end groups, after hydroaging molded samples for 4 weeks at 85° C. and 85% humidity, of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer under a vacuum that is less than 17,000 Pascals and at a torque that is greater than 65%.
17. The process of claim 1 , wherein the amount of unreacted —COOH end groups is at least 30% less than an amount of unreacted —COOH end groups of a comparative compounded hydrostable poly(aliphatic ester-carbonate) prepared by compounding the same amounts of the hydrostable poly(aliphatic ester-carbonate) and the multifunctional epoxide compounding stabilizer under a vacuum that is less than 17,000 Pascals and at a torque that is greater than 65%.
18. The process of claim 1 , wherein
the multifunctional epoxide compound stabilizer is present in an amount of 0.05 to 0.4 wt %,
the vacuum is 60,000 to 70,000 Pascals, and
the torque is 40% to 60%.
19. A compounded hydrostable poly(aliphatic ester-carbonate) prepared by the process of claim 1 , wherein the amount of the multifunctional epoxide compounding stabilizer is 0.1 wt % to 0.2 wt %.
20. The process of claim 1 , wherein the amount of the multifunctional epoxide compounding stabilizer is 0.1 wt % to 0.2 wt %.