A poly(phenylene ether) copolymer comprising first repeating units comprising a C 1-6 alkyl(C 6-30 cycloalkenyl) pendant group; second repeating units different from the first repeating units; and optionally, at least one terminal functional group comprising (meth)acrylate, styrene, -CH 2 -(C 6 H 4)-CH=CH 2, allyl, cyanate ester, glycidyl ether, anhydride, aniline, maleimide, an activated ester, or a combination thereof, wherein the poly(polyphenylene ether) copolymer comprises a copolymer of formula wherein: each occurrence of Q 1 and Q 2 independently comprises halogen, unsubstituted or substituted C 1-12 primary or secondary hydrocarbyl, C 1-12 hydrocarbylthio, C 1-12 hydrocarbyloxy, C 1-6 alkyl(C 6-30 cycloalkenyl), or C 2-12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; each occurrence of Q 3 and Q 4 independently comprises hydrogen, halogen, unsubstituted or substituted C 1 -C 12 primary or secondary hydrocarbyl, C 1 -C 12 hydrocarbylthio, C 1-12 hydrocarbyloxy, C 1-6 alkyl(C 6-30 cycloalkenyl), or C 2-12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; x and y have an average value, and are each independently 0-30, or 0-20, preferably 0-15, still more preferably 0-10, even more preferably 0-8, provided that the sum of x and y is at least 2, preferably at least 3, more preferably at least 4, L is of formula or formula wherein each occurrence of R 3, R 4, R 5, and R 6 is independently hydrogen, halogen, unsubstituted or substituted C 1-12 primary or secondary hydrocarbyl, C 1-12 hydrocarbylthio, C 1-12 hydrocarbyloxy, C 1-6 alkyl(C 6-30 cycloalkenyl), or C 2-12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; w is 0 or 1; and Y is wherein each occurrence of R 7 is independently hydrogen or C 1-12 hydrocarbyl, each occurrence of R 8 and R 9 is independently hydrogen, C 1-12 hydrocarbyl, or R 8 and R 9 together form a C 4-12 cyclohydrocarbylene with the carbon atom, wherein E is 6-100, or 11-80, or 11-60; and each occurrence of R is independently an unsubstituted or substituted C 1-13 alkyl, C 1-13 alkoxy, C 3-6 cycloalkyl, C 3-6 cycloalkoxy, C 6-14 aryl, C 6-10 aryloxy, C 7-13 arylalkylene, or C 7-13 alkylarylene. each occurrence of Q 1 and Q 2 independently comprises halogen, unsubstituted or substituted C 1-12 primary or secondary hydrocarbyl, C 1-12 hydrocarbylthio, C 1-12 hydrocarbyloxy, C 1-6 alkyl(C 6-30 cycloalkenyl), or C 2-12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; each occurrence of Q 3 and Q 4 independently comprises hydrogen, halogen, unsubstituted or substituted C 1 -C 12 primary or secondary hydrocarbyl, C 1 -C 12 hydrocarbylthio, C 1-12 hydrocarbyloxy, C 1-6 alkyl(C 6-30 cycloalkenyl), or C 2-12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; x and y have an average value, and are each independently 0-30, or 0-20, preferably 0-15, still more preferably 0-10, even more preferably 0-8, provided that the sum of x and y is at least 2, preferably at least 3, more preferably at least 4, L is of formula or formula wherein each occurrence of R 3, R 4, R 5, and R 6 is independently hydrogen, halogen, unsubstituted or substituted C 1-12 primary or secondary hydrocarbyl, C 1-12 hydrocarbylthio, C 1-12 hydrocarbyloxy, C 1-6 alkyl(C 6-30 cycloalkenyl), or C 2-12 halohydrocarbyloxy wherein at least two carbon atoms separate the halogen and oxygen atoms; w is 0 or 1; and Y is wherein each occurrence of R 7 is independently hydrogen or C 1-12 hydrocarbyl, each occurrence of R 8 and R 9 is independently hydrogen, C 1-12 hydrocarbyl, or R 8 and R 9 together form a C 4-12 cyclohydrocarbylene with the carbon atom, wherein E is 6-100, or 11-80, or 11-60; and each occurrence of R is independently an unsubstituted or substituted C 1-13 alkyl, C 1-13 alkoxy, C 3-6 cycloalkyl, C 3-6 cycloalkoxy, C 6-14 aryl, C 6-10 aryloxy, C 7-13 arylalkylene, or C 7-13 alkylarylene.