A husk plastic composite comprises a composition including: PVC 10˜20 wt %; vinyl chloride/vinyl acetate (VC/VAC) copolymer 10˜30 wt %; styrene-acrylonitrile copolymer (SAN) 1˜5 wt %; chlorinated polyethylene (CPE) 1˜5 wt %; rice husk powder 10˜40 wt %; inorganic filler 10˜40 wt %; internal lubricant 0.1˜1 wt %; external lubricant 0.1˜1 wt %, and heat stabilizer 1˜5 wt %. The VC/VAC copolymer in the husk plastic composition provided by the present invention can allow the composition to be processed by relatively lower processing temperature to save energy consumption. It will also prevent the husk powder from being burnt or decomposed due to high temperature during the heating process to allow this natural material being added in a large amount in the composition. The present invention can reduce the amount of PVC through a large amount of filling additives but still maintain in good product mechanical properties. The particle size of the husk is preferably in the range of 0.10˜0.60 mm for better hardness, stiffness and wood-like texture in the final product.

A husk plastic composite comprises a composition including: PVC 10˜20 wt %; vinyl chloride/vinyl acetate (VC/VAC) copolymer 10˜30 wt %; styrene-acrylonitrile copolymer (SAN) 1˜5 wt %; chlorinated polyethylene (CPE) 1˜5 wt %; rice husk powder 10˜40 wt %; inorganic filler 10˜40 wt %; internal lubricant 0.1˜1 wt %; external lubricant 0.1˜1 wt %, and heat stabilizer 1˜5 wt %. The VC/VAC copolymer in the husk plastic composition provided by the present invention can allow the composition to be processed by relatively lower processing temperature to save energy consumption. It will also prevent the husk powder from being burnt or decomposed due to high temperature during the heating process to allow this natural material being added in a large amount in the composition. The present invention can reduce the amount of PVC through a large amount of filling additives but still maintain in good product mechanical properties. The particle size of the husk is preferably in the range of 0.10˜0.60 mm for better hardness, stiffness and wood-like texture in the final product.

The present invention provides a post-treatment method of a vinyl chloride-based polymer including: (a) preparing a stream containing vinyl chloride-based polymer powder and unreacted vinyl chloride-based monomers by drying a vinyl chloride-based polymer latex in a drying unit; (b) filtering the stream containing the vinyl chloride-based polymer powder and the unreacted vinyl chloride-based monomers in a filtering unit; and (c) recirculating a gas containing the unreacted vinyl chloride-based monomers discharged from the filtering unit to a latex storage unit.

The present invention provides a post-treatment method of a vinyl chloride-based polymer including: (a) preparing a stream containing vinyl chloride-based polymer powder and unreacted vinyl chloride-based monomers by drying a vinyl chloride-based polymer latex in a drying unit; (b) filtering the stream containing the vinyl chloride-based polymer powder and the unreacted vinyl chloride-based monomers in a filtering unit; and (c) recirculating a gas containing the unreacted vinyl chloride-based monomers discharged from the filtering unit to a latex storage unit.

The present invention provides a post-treatment method of a vinyl chloride-based polymer including: (a) preparing a stream containing vinyl chloride-based polymer powder and unreacted vinyl chloride-based monomers by drying a vinyl chloride-based polymer latex in a drying unit; (b) filtering the stream containing the vinyl chloride-based polymer powder and the unreacted vinyl chloride-based monomers in a filtering unit; and (c) recirculating a gas containing the unreacted vinyl chloride-based monomers discharged from the filtering unit to a latex storage unit.

Provided is a method of preparing a vinyl chloride-acrylic copolymer latex.

Specifically, in one embodiment of the present invention, provided is a method of preparing a latex including vinyl chloride-acrylic copolymer particles with a high degree of polymerization and high molecular weight by performing an emulsion polymerization of a vinyl chloride monomer and an acrylic monomer in the presence of an aqueous dispersion medium and an emulsifier while optimizing a feeding mode of the monomers and the emulsifier.

Provided is a method of preparing a vinyl chloride-acrylic copolymer latex.

Specifically, in one embodiment of the present invention, provided is a method of preparing a latex including vinyl chloride-acrylic copolymer particles with a high degree of polymerization and high molecular weight by performing an emulsion polymerization of a vinyl chloride monomer and an acrylic monomer in the presence of an aqueous dispersion medium and an emulsifier while optimizing a feeding mode of the monomers and the emulsifier.

A polyvinyl alcohol-based resin composition including a modified vinyl alcohol-based polymer (A) in which a polyoxyalkylene unit represented by a general formula (I) is bonded to a polyvinyl alcohol chain and a modified vinyl alcohol-based polymer (B) having a double bond in a polyvinyl alcohol chain.

##STR00001##

(In which: R.sub.1 and R.sub.2 are independently, a methyl group, an ethyl group or a hydrogen atom, and R.sub.3 is an alkyl group or a hydrogen atom. N represents a number of repeating units and is an integer of 5≤n≤70.)

A polyvinyl alcohol-based resin composition including a modified vinyl alcohol-based polymer (A) in which a polyoxyalkylene unit represented by a general formula (I) is bonded to a polyvinyl alcohol chain and a modified vinyl alcohol-based polymer (B) having a double bond in a polyvinyl alcohol chain.

##STR00001##

(In which: R.sub.1 and R.sub.2 are independently, a methyl group, an ethyl group or a hydrogen atom, and R.sub.3 is an alkyl group or a hydrogen atom. N represents a number of repeating units and is an integer of 5≤n≤70.)

The present invention relates to a polyvinyl alcohol-based resin, in which a block character (A) is less than 0.4, and an absorbance (B) at 320 nm in an ultraviolet absorption spectrum in the case of making the polyvinyl alcohol-based resin into a 0.1 wt % aqueous solution is 0.2 or more.