Flame-retardant copolymers of dialkyl (meth)acryloyloxyalkyl phosphate or dialkyl (meth)acryloyloxyalkyl phosphonate monomers and polymer foams based made therefrom

Patent metadata

Field	Value
Publication number	US-2016304692-A1
Application number	US-201315100956-A
Country	US
Kind code	A1
Filing date	Dec 27, 2013
Priority date	Dec 27, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

Polymer foam bodies are made from phosphorus-containing thermoplastic random copolymers of a dialkyl (meth)acryloyloxyalkyl phosph(on)ate. Foam bodies made from these copolymers exhibit increased limiting oxygen indices and surprisingly have good properties. In certain embodiments, the phosphorus-containing thermoplastic copolymer is blended with one or more other polymers and formed into nanofoams.

First claim

1 . A polymer foam body comprising a polymeric matrix containing gas-filled cells, wherein the polymeric matrix comprises a phosphorus-containing, thermoplastic random copolymer of at least one dialkyl (meth)acryloyloxyalkylphosph(on)ate and one or more comonomers, the phosphorus-containing copolymer being characterized in having a weight average molecular weight of at least 60,000 g/mol and 1.5 to 10% by weight phosphorus contributed by the dialkyl(meth)acryloyloxyalkylphosph(on)ate.

2 . The polymer foam body of claim 1 , wherein the dialkyl(meth)acryloyloxyalkylphosph(on)ate is a diethyl(meth)acryloyloxyalkyl phosphate.

3 . The polymer foam body of claim 2 , wherein the diethyl(meth)acryloyloxyalkyl phosphate is diethylmethacryloyloxymethyl phosphate or diethylmethacryloyloxyethyl phosphate.

4 . The polymer foam body of claim 1 , wherein the dialkyl(meth)acryloyloxyalkylphosph(on)ate is a diethyl(meth)acryloyloxyalkyl phosphonate.

5 . The polymer foam body of claim 4 , wherein the dialkyl(meth)acryloyloxyalkylphosphonate is diethylacryloyloxymethyl phosphonate or diethylacryloyloxyethyl phosphonate.

6 . The polymer foam body of claim 1 , wherein the comonomer(s) include at least one alkyl (meth)acrylate.

7 . The polymer foam body of claim 6 , wherein the alkyl (meth)acrylate is methyl methacrylate.

8 . The polymer foam body of claim 1 wherein polymeric matrix further contains at least one thermoplastic, non-phosphorus-containing polymer having a glass transition temperature of at least 70° C.

9 . The polymer foam body of claim 8 wherein the thermoplastic, non-phosphorus-containing polymer is poly(methyl methacrylate) or a non-phosphorus-containing copolymer of methyl methacrylate in which the comonomer(s) have a solubility parameter lower than 20 (megaPascals) 0.5 and the chemical composition of the non-phosphorus-containing copolymer is such that twice the mass fraction of oxygen plus the mass fraction of each of nitrogen, fluorine and silicone in the monomers is greater than 0.2.

10 . The polymer foam body of claim 8 wherein the thermoplastic, non-phosphorus-containing polymer is a styrene-acrylonitrile copolymer.

11 . The polymer foam body of claim 8 wherein the thermoplastic, non-phosphorus-containing polymer is a mixture of (a) at least one (meth)acrylic polymer and (b) at least one (meth)acrylic free acrylonitrile-containing copolymer.

12 . (canceled)

13 . The polymer foam body of claim 1 wherein the polymeric matrix contains an amount of the phosphorus-containing thermoplastic random copolymer to provide the polymeric matrix with 2.5 to 5% by weight phosphorus.

14 . (canceled)

15 . The polymer foam body of any of claims 1 - 14 which is monolithic, has a porosity of at least 50% and has an average cell size of 50 to 1000 nanometers.

16 - 18 . (canceled)

19 . A process for forming the polymer foam body of claim 1 , comprising
A) forming a pressurized mixture of 1) at least one blowing agent in a liquid or supercritical state, 2) a phosphorus-containing, thermoplastic random copolymer of at least one dialkyl (meth)acryloyloxyalkylphosph(on)ate and one or more comonomers, B) depressurizing the mixture whereby the blowing agent volatilizes, and the mixture expands and cools to form the polymer foam body.

20 - 26 . (canceled)

27 . The process of claim 19 , wherein the blowing agent is at least 50 mole-percent carbon dioxide.

28 . The process of claim 27 , wherein the pressure in step A) is such that the carbon dioxide is in a supercritical state, and the temperature in step A) is greater than the glass transition temperature of the mixture; then
B) depressurizing the mixture by reducing the pressure at a rate of at least 100 MPa per second to a pressure of no greater than 500 kPa whereby the mixture expands and cools to form the polymer foam body.

29 . (canceled)

30 . The process of claim 19 , further comprising post-expanding the polymer foam body by heating it to a temperature of 40 to 85° C.

31 . A phosphorus-containing, thermoplastic random copolymer of (I) a dialkyl methacryloyloxyalkyl phosphate wherein the alkyl groups independently contain 1 to 6 carbon atoms and the methacryloyloxyalkyl group is methacryloyloxymethyl or methacryloyloxyethyl, (II) an alkyl methacrylate and optionally (III) one or more additional comonomers, the phosphorus-containing copolymer being characterized in having a weight average molecular weight of at least 30,000 g/mol, a glass transition temperature of at least 70° C. and 2.5 to 10% by weight phosphorus contributed by the diethylmethacryloyloxyalkyl)phosphate.

32 - 33 . (canceled)

Assignees

• Qi Yudong
• Li Yan
• Bunker Shana P
• Costeux Stephane
• Morgan Ted A
• Dow Global Technologies Llc

Inventors

• Qi Yudong
• Li Yan
• Bunker Shana P
• Costeux Stephane
• Morgan Ted A

Classifications

• C08J9/0061

  characterized by the use of several polymeric components · CPC title

• C08J9/122 Primary

  Hydrogen, oxygen, CO2, nitrogen or noble gases · CPC title

• C08J2203/08

  Supercritical fluid · CPC title

• C08F220/14

  Methyl esters {, e.g. methyl (meth)acrylate} · CPC title

• C08J2203/06

  CO2, N2 or noble gases · CPC title