Functionalized process aid blends for cellular PVC
A method of reducing foamed density that results in a foamed polyvinyl chloride (PVC) component exhibiting reduced density. The foamed PVC component contains at least a PVC resin and a process aid blend. The process aid blend contains from 1 weight % to 60 weight % (based on the weight of the blend) of a functionalized process aid, and from 99 weight % to 40 weight % (based on the weight of the blend) of a non-functionalized process aid. The functionalized process aid includes at least one base polymer functionalized with a reactive epoxy, hydroxyl, β-keto ester, β-keto amide, or carboxylic acid functional group. The foamed PVC component containing the process aid blend has a lower density than a reference foamed PVC component made using the same process conditions and additives, but which contains only non-functionalized process aid and not the functionalized process aid.
1. A foamed polyvinyl chloride (PVC) component comprising:
a) a PVC resin;
b) a process aid blend; and
c) a blowing agent;
wherein the process aid blend comprises from about 1% by weight to about 20% by weight of a functionalized process aid and from about 99% by weight to about 80% by weight, of a non-functionalized process aid, based on 100% by weight of the process aid blend,
wherein the functionalized process aid comprises at least one base polymer which is functionalized with from 0.1 wt. % to 35 wt. % of a reactive epoxy, hydroxyl, β-keto ester, β-keto amide, or carboxylic acid functional group or mixture thereof based on a total weight of the functionalized process aid;
wherein the process aid blend is present in an amount from 0.1 to 15 parts per hundred (phr) by weight of the PVC resin; and
wherein the foamed PVC component comprising the process aid blend has a lower density than a reference foamed PVC component comprising a 100% non-functionalized process aid, and wherein the foamed PVC component comprising the process aid blend and the reference foamed PVC component comprising the 100% non-functionalized process aid are made using the same process conditions and additives.
2. The foamed PVC component according to claim 1 , wherein the foamed PVC component comprising the process aid blend has a density that is at least 2 percent less than the density of the reference foamed PVC component.
3. The foamed PVC component according to claim 1 , wherein the base polymer of the functionalized process aid is derived from one or more monomers comprising (meth) acrylic-containing monomers.
4. The foamed PVC component according to claim 1 , wherein the base polymer of the functionalized process aid is derived from i) one or more monomers comprising (meth) acrylic-containing monomer and ii) at least one monomer selected from the group consisting of vinyl-containing monomers, styrene and styrene derivatives, olefins, dienes, and mixtures thereof.
5. The foamed PVC component according to claim 1 , wherein the reactive epoxy, hydroxyl, ß-keto ester, ß-ketoamide, or carboxylic acid functional group is derived from hydroxyl-substituted alkyl esters of (meth) acrylic acid; vinyl esters of linear or branched carboxylic acids; unsaturated C 3 -C 6 monocarboxylic acids and unsaturated C 4 -C 6 dicarboxylic acids; β-keto esters of (meth)acrylic acids; β-keto amides of (meth)acrylic acids; epoxy group-containing monomers; or mixtures thereof.
6. The foamed PVC component according to claim 1 , wherein the non-functionalized process aid comprises an acrylic polymer or an acrylic copolymer.
7. The foamed PVC component according to claim 1 , wherein the functionalized process aid has a weight average molecular weight of at least 50,000 g/mol.
8. The foamed PVC component according to claim 1 , wherein the non-functionalized process aid comprises a polymer.
9. The foamed PVC component according to claim 8 , wherein the non-functionalized process aid comprises chlorinated polyethylene (PE-C).
10. The foamed PVC component according to claim 1 , wherein the foamed PVC component is a building material or flooring.
11. A method of making a foamed polyvinyl chloride (PVC) component, wherein the method comprises:
combining:
a) a polyvinyl chloride (PVC) resin,
b) a process aid blend, wherein the process aid blend comprises from about 1% by weight to about 20% by weight of a functionalized process aid and from about 99% by weight to about 80% by weight of a non-functionalized process aid based on 100% by weight of the process aid blend; and
c) a blowing agent;
to form a foamable PVC composition; and
processing the foamable PVC composition to form the foamed PVC component;
wherein the functionalized process aid comprises at least one base polymer which is functionalized with from 0.1 wt. % to 35 wt. % of a reactive epoxy, hydroxyl, β-keto ester, β-keto amide, or carboxylic acid functional group, or mixture thereof based on a total weight of the functionalized process aid; and
wherein the foamed PVC component comprising the process aid blend has a lower density than a reference foamed PVC component comprising a 100% non-functionalized process aid, and wherein the foamed PVC component comprising the process aid blend and the reference foamed PVC component comprising the 100% non-functionalized process aid are made using the same process conditions and additives; and
wherein the process aid blend is present in an amount from 0.1 to 15 parts per hundred (phr) by weight of the PVC resin.
12. The method of making a foamed PVC component according to claim 11 , wherein the foamed PVC component comprising the process aid blend has a density that is at least 2 percent less than the density of the reference foamed PVC component.
13. The method of making a foamed PVC component according to claim 11 , wherein the base polymer of the functionalized process aid is derived from one or more monomers comprising (meth)acrylic-containing monomers.
14. The method of making a foamed PVC component according to claim 11 , wherein the base polymer of the functionalized process aid is derived from i) one or more monomers comprising (meth)acrylic-containing monomer and ii) at least one monomer selected from the group consisting of vinyl-containing monomers, styrene and styrene derivatives, olefins, dienes, and mixtures thereof.
15. The method of making a foamed PVC component according to claim 11 , wherein the reactive epoxy, hydroxyl, ß-keto ester, ß-ketoamide, or carboxylic acid functional group is derived from hydroxyl-substituted alkyl esters of (meth) acrylic acid; vinyl esters of linear or branched carboxylic acids; unsaturated C 3 -C 6 monocarboxylic acids and unsaturated C 4 -C 6 dicarboxylic acids; β-keto esters of (meth)acrylic acids; β-keto amides of (meth)acrylic acids; epoxy group-containing monomers; or mixtures thereof.
16. The method of making a foamed PVC component according to claim 15 , wherein the base polymer is functionalized with a reactive epoxy functional group derived from glycidyl methacrylate, or glycidyl acrylate, or mixtures thereof.
17. The method of making a foamed PVC component according to claim 11 , wherein the non-functionalized process aid comprises an acrylic polymer or an acrylic copolymer.
18. The method of making a foamed PVC component according to claim 11 , wherein the functionalized process aid has a weight average molecular weight of at least 50,000 g/mol.
19. The method of making a foamed PVC component according to claim 11 , wherein the non-functionalized process aid comprises a polymer.
20. The method of making a foamed PVC component according to claim 19 , wherein the non-functionalized process aid comprises chlorinated polyethylene (PE-C).
21. The method of making a foamed PVC component according to claim 11 , wherein the foamed PVC component is a building or flooring material.