Foamable polymeric compositions

Claim 2

A foamable thermoplastic synthetic resin composition containing a polymer selected from the group consisting of styrenic and olefin polymers, a blowing agent and at least one glycol ester compound of the formula I below in an amount of 0.1 to 10% by weight in respect to the resin: [(R.sub.1 CO).sub.l ·(OR.sub.2).sub.m ·O].sub.n ·M (I) wherein, R 1 is an aliphatic hydrocarbon radical with 10 to 24 carbons; R 2 is an aliphatic polyvalent alcohol resin residue with 1 to 5 carbons; l is a positive integer greater than 1 and less than the (alcohol valence of the R 2 group) -1; m is a positive integer greater than 1 satisfying the following equation: ##EQU4## n is a positive integer of from 1 to 3; and M is a residue of boric acid or phosphoric acid.

Claim 3

The foamable thermoplastic resin composition of claim 1 wherein the thermoplastic synthetic resin is polyethylene or a copolymer of ethylene with one or more other monomers copolymerizable therewith.

Claim 4

A low density, closed-cell synthetic resin foam article derived from the foamable thermoplastic resin composition of claim 1.

Claim 5

In a process for preparing a low density, closed-cell synthetic resin foam article by admixing a resin selected from the group consisting of styrenic and olefin polymers in molten form and under elevated pressure with a blowing agent and by thereafter releasing the resulting mixture to a zone of lower temperature and pressure, the improvement comprising incorporating into said molten resin/blowing agent mixture, prior to its release to said lower temperature and pressure zone, from 1.0 to about 10 weight percent based upon the weight of said resin of a glycol ester compound of the formula I below: [(R.sub.1 CO).sub.l ·(OR.sub.2).sub.m ·O].sub.n ·M (I) wherein, R 1 is an aliphatic hydrocarbon radical with 10 to 24 carbons; R 2 is an aliphatic polyvalent alcohol resin residue with 1 to 5 carbons; l is a positive integer greater than 1 and less than the (alcohol valence of the R 2 group) -1; m is a positive integer greater than 1 satisfying the following equation: ##EQU5## n is a positive integer of from 1 to 3; and M is a residue of boric acid or phosphoric acid.

Claim 6

In a process for preparing a low density, closed-cell synthetic resin foam article by admixing a resin selected from the group consisting of styrenic and olefin polymers in molten form and under elevated pressure with a blowing agent and by thereafter releasing the resulting mixture to a zone of lower temperature and pressure, the improvement comprising incorporating into said molten resin/blowing agent mixture, prior to its release to said lower temperature and pressure zone, from 1.0 to about 10 weight percent based upon the weight of said resin of a glycol ester compound of the formula I below: [(R.sub.1 CO).sub.l ·(OR.sub.2).sub.m ·O].sub.n ·M (I) wherein, R 1 is an aliphatic hydrocarbon radical with 10 to 24 carbons; R 2 is an aliphatic polyvalent alcohol resin residue with 1 to 5 carbons; l is a positive integer greater than 1 and less than the (alcohol valence of the R 2 group) -1; m is a positive integer greater than 1 satisfying the following equation: ##EQU5## n is a positive integer of from 1 to 3; and M is a residue of boric acid or phosphoric acid.