Polymer blends and method for making the same
The present invention pertains to solid polymer blends obtainable from starting materials comprising glycerine, an ABS polymer, a PBT polymer, a PET polymer, and optionally polymer additives. Further, the present invention pertains to particles of the polymer blend and their use for the manufacture of polyurethanes, in particular, polyurethane foams.
1 . A solid polymer blend product obtainable by a process consisting of the following steps:
a) providing a mixture comprising:
0.5 to 7 percent by weight of glycerine;
5 to 25 percent by weight of an ABS (acrylonitrile-butadiene-styrene) copolymer;
5 to 25 percent by weight of a PBT (polybutylene terephthalate) polymer;
48 to 89.5 percent by weight of a PET (polyethylene terephthalate) polymer; and
0 to 5 percent by weight of polymer additives;
wherein the sum of the amounts of the components listed above is 100 percent by weight;
b) subjecting the mixture from step (a) to an extrusion process at elevated temperatures;
c) cooling and granulating the product from step (b) into a granulate; and
optionally
d) subjecting the granulate from step (c) to a milling step to obtain the product in the form of particles having a mean average particle size of from 0.1 μm to 200 μm.
2 . The polymer blend product according to claim 1 , wherein the ABS copolymer is selected from the group consisting of ABS blend type polymer or ABS graft polymer.
3 . The polymer blend product according to claim 1 , wherein the polymer additives are selected from the group consisting of antioxidants, light stabilizers, lubricants, flame retardants, fillers, dyes, or pigments.
4 . The polymer blend product according to claim 1 , wherein the PET polymer is a commercially available PET having a molecular weight (Mw) in the range of from 20,000 to 100,000.
5 . The polymer blend product according to claim 4 , wherein the PET polymer is a recycled PET or a scrap PET.
6 . The polymer blend product according to claim 1 , wherein the product is present in the form of micronized particles with a mean average particle size of from 0.1 μm to 200 μm.
7 . The polymer blend product according to claim 1 , wherein the product is present in the form of micronized particles with a mean average particle size of from 1 μm to 25 μm.
8 . A process for the preparation of a solid polymer blend product according to claim 1 , the process comprising the steps of:
a) providing a mixture comprising:
0.5 to 7 percent by weight of glycerine;
5 to 25 percent by weight of an ABS (acrylonitrile-butadiene-styrene) copolymer;
5 to 25 percent by weight of a PBT (polybutylene terephthalate) polymer;
48 to 89.5 percent by weight of a PET (polyethylene terephthalate) polymer; and
0 to 5 percent by weight of polymer additives;
wherein the sum of the amounts of the components listed above is 100 percent by weight;
b) subjecting the mixture from step (a) to an extrusion process at elevated temperatures;
c) cooling and granulating the product from step (b) into a granulate; and
optionally
d) subjecting the granulate from step (c) to a milling step to obtain the product in the form of particles having a mean average particle size of from 0.1 μm to 200 μm.
9 . The process according to claim 8 , wherein the extrusion process of step (b) is performed at a temperature in the range from 150 to 250° C.
10 . The process according to claim 8 , wherein the extrusion process of step (b) is performed at a temperature in the range from 170 to 190° C.
11 . The process according to claim 8 , wherein the elevated temperature during the extrusion step (b) is maintained for 10 minutes or less.
12 . The process according to claim 8 , wherein the elevated temperature during the extrusion step (b) is maintained for 5 minutes or less.
13 . The process according to claim 8 , wherein the elevated temperature during the extrusion step (b) is maintained for 3 minutes or less.
14 . The process according to claim 8 , wherein the extrusion process of step (b) is performed with a heatable single-screw extruder.
15 . The process according to claim 8 , wherein the extrusion process of step (b) is performed with a heatable twin-screw extruder.
16 . The process according to claim 8 , wherein the milling step in step (d) comprises jet-milling of the granulate obtained in step (c) with a jet mill, and wherein the jet mill is an opposed jet mill.
17 . The process according to claim 8 , wherein the milling step in step (d) comprises jet-milling of the granulate obtained in step (c) with a jet mill, and wherein the jet mill is a fluidized-bed jet mill.
18 . A process for producing polyurethanes comprising reacting a solid polymer blend product of claim 1 with isocyanates.
19 . The process according to claim 18 , further comprising including polyols.
20 . The process according to claim 18 , wherein the polyurethane is a polyurethane foam.