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US 9,428,601 B2Granted
Method of preparing vinyl chloride polymers having superior processability
AssigneeLG Chem, Ltd.
InventorsSeong-Yong Ahn, Kyung-Hyun Kim, Young-Suk Kim, Jong-Hun Cho, Chang-Ryang Jang
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Abstract
The present invention relates to a method of preparing a vinyl chloride polymer, and more precisely, a method of preparing a vinyl chloride polymer having excellent processability by raising a final polymerization temperature up to 5˜20° C. from an first polymerization temperature.
Claims17
A method of preparing a vinyl chloride homopolymer comprising:
- polymerizing vinyl chloride monomer in the presence of a solvent, a polymerization initiator, a protective colloid auxiliary, and a pH regulator at a polymerization temperature of 30° C. to 75° C.,
- wherein 120 to 150 weight part of the solvent, 0.02 to 0.2 weight part of the polymerization initiator, 0.03 to 5 weight part of the protective colloid auxiliary and 0.01 to 1.5 weight part of the pH regulator are added to 100 weight part of the vinyl chloride monomer;
- adding a first amount of additional vinyl chloride monomer when a polymerization conversion rate ranges from 30% to 40% at the polymerization temperature;
- polymerizing the first additional vinyl chloride monomer at the polymerization temperature;
- adding a second amount of additional vinyl chloride monomer and an antioxidant to the reactor when the polymerization conversion rate reaches 60 to 70%;
- and
- polymerizing the second amount of additional vinyl chloride monomer at a temperature that is 5° C. to 20° C. higher than the polymerization temperature to obtain an average polymerization degree of 700 to 1300;
- wherein the antioxidant is added in an amount of 0.001 to 0.03 weight part for 100 weight part of the vinyl chloride monomer, and
- wherein the polymerization initiator is one or more compounds selected from the group consisting of dicumyl peroxide, dilauryl peroxide, di-2-ethylhexylperoxydicarbonate and t-butylperoxyneodecanoate.
6 more elements
A method of preparing a vinyl chloride polymer comprising:
- polymerizing vinyl chloride monomer in the presence of a solvent, a polymerization initiator, a protective colloid auxiliary, and a pH regulator at a polymerization temperature of 30° C. to 75° C.,
- wherein 120 to 150 weight part of the solvent, 0.02 to 0.2 weight part of the polymerization initiator, 0.03 to 5 weight part of the protective colloid auxiliary and 0.01 to 1.5 weight part of the pH regulator are added to 100 weight part of the vinyl chloride monomer;
- adding a first amount of additional vinyl chloride monomer when a polymerization conversion rate ranges from 30% to 40% at the polymerization temperature;
- polymerizing the first additional vinyl chloride monomer at the polymerization temperature;
- adding a second amount of additional vinyl chloride monomer and an antioxidant to the reactor when the polymerization conversion rate reaches 60 to 70%;
- and
- polymerizing the second amount of additional vinyl chloride monomer at a temperature that is 5° C. to 20° C. higher than the polymerization temperature to obtain an average polymerization degree of 700 to 1300;
- wherein the antioxidant is added in an amount of 0.001 to 0.03 weight part for 100 weight part of the vinyl chloride monomer, and
- wherein the polymerization initiator is one or more compounds selected from the group consisting of dicumyl peroxide, dilauryl peroxide, di-2-ethylhexylperoxydicarbonate and t-butylperoxyneodecanoate,
- wherein a bulk specific gravity of the vinyl chloride polymer ranges from 0.573 grams per cubic centimeter (g/cc) to 0.579 g/cc.
7 more elements
Dependencies are inferred from the claim text.