Polyvinyl alcohol-based polymer
AssigneeDenka Company Limited
InventorAkihiro Yamashita
Life of this patent
Estimating the term…
Abstract
A PVA excellent in resistance to melting at high temperature is provided. The polyvinyl alcohol-based polymer is a saponificated product of a homopolymer composed of a vinyl ester monomer, a copolymer of a vinyl ester monomer and a monofunctional monomer other than the vinyl ester, a copolymer of a vinyl ester monomer and a polyfunctional monomer, or a copolymer of a vinyl ester monomer, a monofunctional monomer other than vinyl ester, and a polyfunctional monomer has a particle size of 50 nm or more at a cumulative frequency of 50% in particle size distribution by dynamic light scattering measurement of a 0.4 mass % aqueous solution of the polyvinyl alcohol-based polymer at 25° C.
Claims7
A polyvinyl alcohol-based polymer, as a saponificated product of:
- a homopolymer composed of a vinyl ester monomer;
- a copolymer of a vinyl ester monomer and a monofunctional monomer other than the vinyl ester;
- a copolymer of a vinyl ester monomer and a polyfunctional monomer;
- or
- a copolymer of a vinyl ester monomer, a monofunctional monomer other than vinyl ester, and a polyfunctional monomer,
- wherein the polyvinyl alcohol-based polymer has a particle size of 50 nm or more at a cumulative frequency of 50% in particle size distribution by dynamic light scattering measurement of a 0.4 mass % aqueous solution of the polyvinyl alcohol-based polymer at 25° C., and
- wherein an average particle size obtained from the dynamic light scattering measurement of a 0.4 mass % aqueous solution of the polyvinyl alcohol-based polymer at 25° C. is 60 nm or more.
Dependencies are inferred from the claim text.