Temperature resistant microporous film

Claim 1

A process for at least partially coating a microporous film of a first polymer with the layer of a second polymer comprising: applying a mixture comprising a precursor monomer of the second polymer and catalyst to the portions of a surface of the microporous film to be coated, wherein said precursor monomer is at least one monomer selected from the group of monomers represented by formulas (I) and (II), wherein formula (I) is ##STR4## wherein said formula (I) X is selected from the group consisting of ##STR5## --S--, and --O--; R 1 , is selected from the group consisting of hydrogen, --C(O)OH,--C(O)C(O)OH, --SO 3 H, --C(O)H, --I, and --Br; R 2 is selected from the group consisting of hydrogen, a C 1 to C 10 alkyl group, --C(O)OH, and a halogen; R 3 is selected from the group consisting of hydrogen, a C 1 to C 10 alkyl group, --C(O)OH, and a halogen; R 4 is selected from the group consisting of hydrogen, --C(O)OH, --C(O)OH, --SO 3 H, --C(O)H, --I, and --Br, wherein R 1 and R 4 are not both hydrogen, and wherein formula (II) is ##STR6## wherein formula (II) X 1 and X 2 are the same or different and are selected from a group consisting of --S--, --O--, >N--R 5 , R 6 and R 7 are the same or different, and are selected from the group consisting of hydrogen and C 1 to C 2 alkyl, and wherein R 5 is selected from the group consisting of hydrogen, alkyl, aryl and alkoxy; converting the precursor monomers to corresponding polymerizable monomers; and subjecting the film to conditions under which the catalyst causes the monomers to polymerize, forming the second polymer.