RECYCLABLE POLYMER FOAMS
Embodiments of the present disclosure are directed to a foam, which may comprise the crosslinked reaction product of a maleic anhydride grafted olefin block copolymer (MAH-g-OBC) and a secondary alcohol. The foam may have a density less than or equal to 0.2 g/cc.
1 . A foam comprising the crosslinked reaction product of:
maleic anhydride grafted olefin block copolymer (MAH-g-OBC); and
secondary alcohol,
wherein the foam has a density less than or equal to 0.2 g/cc.
2 . The foam of claim 1 , wherein the foam comprises a blend of the MAH-g-OBC and one or more of polyolefin elastomers, ethylene vinyl acetate copolymer, and low density polyethylene.
3 . The foam of claim 1 , wherein the secondary alcohol is defined by the following formula:
wherein, R1 and R4 each independently represent a chain or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group, or an aromatic group; R2 and R3 each independently represents a linear or cyclic alkylene group having 1 to 20 carbon atoms, a carbonyl group, an aromatic group, or an oxy group; d and e are integers of 0 or more; and f is an integer of 1 or more.
4 . The foam of claim 1 , wherein the secondary alcohol comprises 2,5-hexanediol.
5 . The foam of claim 1 , wherein the foam has a rebound % of greater than or equal to 60.
6 . The foam of claim 1 , wherein the foam density is less than or equal to 0.1 g/cc.
7 . The foam of claim 1 , wherein the MAH-g-OBC has a grafting level from 0.1 to 2.0 wt. % maleic anhydride.
8 . The foam of claim 1 , wherein the OBC is an ethylene/alpha-olefin block copolymer.
9 . The foam of claim 8 , wherein the alpha-olefin is octene.
10 . The foam of claim 8 , wherein the ethylene/alpha-olefin block copolymer comprises greater than 50 mol. % ethylene monomer.
11 . The foam of claim 1 , wherein the foam comprises 98 to 99.999 wt. % MAH-g-OBC and 0.001 to 2 wt. % secondary alcohol.
12 . A foaming process:
physically foaming a thermoreversible crosslinkable composition to form the foam of claim 1 , wherein the thermoreversible crosslinkable composition comprises the MAH-g-OBC, and the secondary alcohol.
13 . The foaming process of claim 12
hot pressing the foam to remove the air and form solid film pieces;
compression molding the solid film pieces into one or more plates;
physically foaming the plates to produce a recycled foam.
14 . The foaming process of claim 12 , wherein the recycled foam comprises a blend of recycled foam material and virgin foam material.
15 . The foaming process of claim 12 , wherein the physical foaming uses a physical blowing agent, the physical blowing agent comprising CO 2 or N 2 .