Cross-linkable polymer compositions

A method of cross-linking or chain extending a polymeric material in a shaped article, wherein the shaped article comprises a polymer composition comprising the polymeric material, the method comprising:

• heating the shaped article in at least one heating step in which the shaped article is heated in air from a first temperature T1 to a second temperature T2>T1, such that the Tg of the polymeric material which is the mid-point glass transition temperature (Tg) of the polymeric material as measured by differential scanning calorimetry (DSC) (first heat) heating at 20° C/min from 40° C. to 300° C. at any time during the heating step increases during such heating step, wherein:
• the first temperature T1 is greater than or equal to Tg(i)-20° C. and less than Tg(i)+5° C., said Tg(i) being the glass transition temperature of the polymeric material before such heating step,
• the second temperature T2 is greater than Tg(t) -20° C. and less than or equal to Tg(t)+5° C., said Tg(t) being the glass transition temperature of the polymeric material subsequent to such associated heating step, and
• further wherein the polymeric material comprises a silane-modified poly(arylene ether) polymer (Si-PAE) of formula (I):
• wherein:
• Q is independently selected from the group consisting of a sulfone group [—S(═O)2—] and a ketone group [—C(═O)—];
• T, equal to each other, is selected from the group consisting of a bond, —CH2—;
• —O—;
• —SO2—;
• —S—;
• —C(O)—;
• —C(CH3)2—;
• —C(CF3)2—;
• —C(═CCl2)—;
• —C(CH3)(CH2CH2COOH)—;
• —N═N—;
• —RaC═CRb—, where each Ra and Rb, independently of one another, is a hydrogen or a C1-C12-alkyl, C1-C12-alkoxy, or C6-C18-aryl group;
• —(CH2)p— and —(CF2)p— with p being an integer from 1 to 6;
• an aliphatic divalent group, linear or branched, of up to 6 carbon atoms;
• and combinations thereof;
• n is an integer ranging from 2 to 100;
• each R is independently selected from the group consisting of a halogen, an alkyl, an alkenyl, an alkynyl, an aryl, an ether, a thioether, a carboxylic acid, an ester, an amide, an imide, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, an alkali or alkaline earth metal phosphonate, an alkyl phosphonate, an amine, a quaternary ammonium, an epoxy, a norbornene, an acrylate, an olefin, a silane, and a group E;
• each i is independently selected from an integer ranging from 0 to 4;
• each E is independently selected from the group consisting of moieties of formula (II) :
• wherein:
• each Z is independently selected from the group consisting of an alkyl, an alkoxy, and an —OH group, provided that at last one of Z is an alkoxy or an —OH group;
• L is selected from the group consisting of a bond, an alkyl, an aryl, and an arylalkyl, wherein the alkyl, aryl, and arylalkyl are optionally substituted with one or more heteroatoms;
• and
• Y is a selected from the group consisting of a —CH2— and a —(C═O)NH— group.