An optical film including a polymer including a repeating unit A including a repeating unit represented by the following Chemical Formulas 1 to 3, or a combination thereof; and a repeating unit B derived from a monomer having an unsaturated bond copolymerizable with the repeating unit A, wherein the optical film has a short wavelength dispersion of an in-plane phase-difference value (R.sub.e) (450 nm/550 nm) ranging from about 0.81 to about 1.20, and a long wavelength dispersion of an in-plane phase-difference value (R.sub.e) (650 nm/550 nm) ranging from about 0.90 to about 1.18: ##STR00001##
wherein, in Chemical Formulas 1 to 3, the variables R.sup.1 to R.sup.21 are defined herein.

An optical film including a polymer including a repeating unit A including a repeating unit represented by the following Chemical Formulas 1 to 3, or a combination thereof; and a repeating unit B derived from a monomer having an unsaturated bond copolymerizable with the repeating unit A, wherein the optical film has a short wavelength dispersion of an in-plane phase-difference value (R.sub.e) (450 nm/550 nm) ranging from about 0.81 to about 1.20, and a long wavelength dispersion of an in-plane phase-difference value (R.sub.e) (650 nm/550 nm) ranging from about 0.90 to about 1.18: ##STR00001##
wherein, in Chemical Formulas 1 to 3, the variables R.sup.1 to R.sup.21 are defined herein.

To provide: an electrolyte material having high oxygen permeability as compared with conventional ones; a membrane electrode assembly for a polymer electrolyte fuel cell excellent in power generation characteristics as compared with conventional ones; a liquid composition suitable for forming a catalyst layer for the membrane electrode assembly; and a fluorinated branched polymer useful as e.g. a raw material of the electrolyte material. The electrolyte material comprises a fluoropolymer (H)1 having a structural unit (u1) that has an ionic group and a structural unit (u2) that has an alicyclic structure, wherein the fluoropolymer (H)1 is composed of a branched molecular chain, and has a segment (A)3 comprising a molecular chain having the structural unit (u1) and a segment (B)2 composed of a molecular chain having the structural unit (u2), and the ion exchange capacity of the segment (B)2 is smaller than the ion exchange capacity of the segment (A)3.

To provide: an electrolyte material having high oxygen permeability as compared with conventional ones; a membrane electrode assembly for a polymer electrolyte fuel cell excellent in power generation characteristics as compared with conventional ones; a liquid composition suitable for forming a catalyst layer for the membrane electrode assembly; and a fluorinated branched polymer useful as e.g. a raw material of the electrolyte material. The electrolyte material comprises a fluoropolymer (H)1 having a structural unit (u1) that has an ionic group and a structural unit (u2) that has an alicyclic structure, wherein the fluoropolymer (H)1 is composed of a branched molecular chain, and has a segment (A)3 comprising a molecular chain having the structural unit (u1) and a segment (B)2 composed of a molecular chain having the structural unit (u2), and the ion exchange capacity of the segment (B)2 is smaller than the ion exchange capacity of the segment (A)3.

Poly(cyclic vinyl ethers) (PCVEs), compositions of same, methods of making same, and uses of same. In various examples, PCVEs (e.g., homopolymers and/or copolymers) comprise repeat units comprising cyclic vinyl ether (CVE) groups in the backbone (e.g., poly(2,3-dihydrofuran) and/or poly(3,4-dihydropyran)). In various examples, PCVE homopolymers comprise molecular weights (Mn and/or Mw) of 200 kilodalton (kD) or greater. In various examples, PCVE copolymers (e.g., random or block) comprise one or more CVE group(s) and/or additional (e.g., acyclic vinyl ether (AVE) and/or styrenic) group(s)). A method of preparing PCVEs comprises polymerizing monomers comprising CVE groups (e.g., 2,3-dihydrofuran and/or 3,4-dihydropyran). In various examples, pentakis(carbonylcyclopentadienes) (PCCPs) and/or hydrogen bond donors are polymerization catalysts and/or initiators. various examples, PCVEs are biorenewable, recyclable, thermoplastic materials that exhibit desirable optical clarity, desirable barrier properties to, e.g., oxygen, carbon dioxide, and water, and find uses in food packaging, windows, and the like.

Poly(cyclic vinyl ethers) (PCVEs), compositions of same, methods of making same, and uses of same. In various examples, PCVEs (e.g., homopolymers and/or copolymers) comprise repeat units comprising cyclic vinyl ether (CVE) groups in the backbone (e.g., poly(2,3-dihydrofuran) and/or poly(3,4-dihydropyran)). In various examples, PCVE homopolymers comprise molecular weights (Mn and/or Mw) of 200 kilodalton (kD) or greater. In various examples, PCVE copolymers (e.g., random or block) comprise one or more CVE group(s) and/or additional (e.g., acyclic vinyl ether (AVE) and/or styrenic) group(s)). A method of preparing PCVEs comprises polymerizing monomers comprising CVE groups (e.g., 2,3-dihydrofuran and/or 3,4-dihydropyran). In various examples, pentakis(carbonylcyclopentadienes) (PCCPs) and/or hydrogen bond donors are polymerization catalysts and/or initiators. various examples, PCVEs are biorenewable, recyclable, thermoplastic materials that exhibit desirable optical clarity, desirable barrier properties to, e.g., oxygen, carbon dioxide, and water, and find uses in food packaging, windows, and the like.

A polymer is defined as comprising repeat units having a cyclic acetal structure fused to an aromatic ring and repeat units derived from an onium salt compound containing a fluorosulfonic acid anion having a polymerizable group and an iodized aromatic ring structure. A chemically amplified resist composition comprising the polymer has advantages including high sensitivity, high contrast, improved lithography properties, e.g., EL, LWR, CDU and DOF, collapse resistance during fine pattern formation, and etch resistance after development.

A polymer is defined as comprising repeat units having a cyclic acetal structure fused to an aromatic ring and repeat units derived from an onium salt compound containing a fluorosulfonic acid anion having a polymerizable group and an iodized aromatic ring structure. A chemically amplified resist composition comprising the polymer has advantages including high sensitivity, high contrast, improved lithography properties, e.g., EL, LWR, CDU and DOF, collapse resistance during fine pattern formation, and etch resistance after development.

The present disclosure describes functional oligomers or functional polymers. The functional oligomers or functional polymers may contain functional groups, e.g., OH and/or CHO. The functional oligomers or functional polymers may be obtained from hydrolyzing certain copolymers and may be soluble in commercially available solvents. The copolymers may be thermosetting polymers. The functional oligomers and functional polymers may be useful for recycling thermosetting polymers and may be useful as starting materials for preparing additional oligomers or polymers.

The present disclosure describes functional oligomers or functional polymers. The functional oligomers or functional polymers may contain functional groups, e.g., OH and/or CHO. The functional oligomers or functional polymers may be obtained from hydrolyzing certain copolymers and may be soluble in commercially available solvents. The copolymers may be thermosetting polymers. The functional oligomers and functional polymers may be useful for recycling thermosetting polymers and may be useful as starting materials for preparing additional oligomers or polymers.