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US 8,981,019 B2Granted
Method for producing methacrylic-based polymer
AssigneeMitsubishi Rayon Co., Ltd.
InventorsHisaaki Yoshimura, Masahiro Hayashida, Daisuke Nonaka, Yusuke Morita, Mitsuhiro Matsuo
Life of this patent
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Abstract
There is provided a method capable of producing a methacrylic-based polymer excellent in pyrolysis resistance and excellent in fabricability in a high productivity. The method for producing a methacrylic-based polymer includes the following steps (1) and (2): step (1) of using a complete mixing reactor (A) to thereby obtain the first syrup, including specific steps; step (2) of using a reaction apparatus (D) including a plug flow mixer (B) and a plug flow reactor (C) to thereby obtain the second syrup, including specific steps.
Claims5
A method for producing a methacrylic-based polymer, comprising the following Steps (1) and (2):
- Step (1):
- using a complete mixing reactor (A) to thereby obtain a first syrup with the step comprising the following steps (1)-1, (1)-2 and (1)-3:
- (1)-1:
- continuously feeding a monomer mixture containing 80 to 99.9 mass % of methyl methacrylate and 0.1 to 20 mass % of an alkyl acrylate, 0.01 to 1.0 parts by mol of a mercaptan based on 100 parts by mol of the monomer mixture, and a first radical polymerization initiator (a) in an amount satisfying the following formula (1), to the complete mixing reactor (A):
- 5.0×10−5<α≦1.75×β×10−6+6.0×10−5 (1)
- wherein in the formula (1), α is a number of moles of the first radical polymerization initiator (a) based on 1 mol of the monomer mixture;
- and β is a proportion (mass %) of an alkyl acrylate unit in the methacrylic-based polymer to be produced;
- (1)-2:
- carrying out stirring and mixing at a temperature of the complete mixing reactor (A) interior of 110 to 160° C., and carrying out polymerization so that a content of a polymer of the monomer mixture becomes 40 to 60 mass %;
- and
- (1)-3:
- continuously obtaining the first syrup from the complete mixing reactor (A);
- Step (2):
- using a reaction apparatus (D) comprising a plug flow mixer (B) and a plug flow reactor (C) to thereby obtain a second syrup, wherein a second radical polymerization initiator (c) is added to the first syrup with the plug flow mixer (B) having an inner wall temperature set at the temperature of the complete mixing reactor (A) interior or higher and 230° C. or lower to thereby make a syrup mixture, and then polymerization is carried out by the plug flow reactor (C) to obtain the second syrup.
11 more elements
A method for producing a methacrylic-based polymer, comprising the following Steps (1) to (3):
- Step (1):
- using a complete mixing reactor (A) to thereby obtain a first syrup with the step comprising the following steps (1)-1, (1)-2 and (1)-3:
- (1)-1:
- continuously feeding a monomer mixture containing 80 to 99.9 mass % of methyl methacrylate and 0.1 to 20 mass % of an alkyl acrylate, 0.01 to 1.0 parts by mol of a mercaptan based on 100 parts by mol of the monomer mixture, and a first radical polymerization initiator (a) in an amount satisfying the following formula (1), to the complete mixing reactor (A):
- 5.0×10−5<α≦1.75×β×10−6+6.0×10−5 (1)
- wherein in the formula (1), α is a number of moles of the first radical polymerization initiator (a) based on 1 mol of the monomer mixture;
- and β is a proportion (mass %) of an alkyl acrylate unit in the methacrylic-based polymer to be produced;
- (1)-2:
- carrying out stirring and mixing at a temperature of the complete mixing reactor (A) interior of 110 to 160° C., and carrying out polymerization so that a content of a polymer of the monomer mixture becomes 40 to 60 mass %;
- and
- (1)-3:
- continuously obtaining the first syrup from the complete mixing reactor (A);
- Step (2):
- using a reaction apparatus (D) comprising a plug flow mixer (B) and a plug flow reactor (C) to thereby obtain a second syrup with the step comprising the following steps of (2)-1, (2)-2 and (2)-3:
- (2)-1:
- adding a second radical polymerization initiator (c) satisfying the following conditions (i) to (iii) to the first syrup, and carrying out mixing with the plug flow mixer (B) having an inner wall temperature set at the temperature of the complete mixing reactor (A) interior or higher and 230° C. or lower to thereby make a syrup mixture:
- Condition (i):
- a half-life period of the second radical polymerization initiator (c) at an inner wall temperature of the plug flow mixer (B) is 1,000 sec or shorter;
- Condition (ii):
- a half-life period of the second radical polymerization initiator (c) at an inner wall temperature of the reactor (C) is 1,000 sec or shorter;
- and
- Condition (iii):
- an amount of the second radical polymerization initiator (c) added satisfies the following formula (2):
- 1.0×10−6<γ≦0.25×β×10−6+5.0×10−5 (2)
- wherein in the formula (2), γ is a number of moles of the second radical polymerization initiator (c) based on 1 mol of the monomer mixture;
- and β is a proportion (mass %) of an alkyl acrylate unit in the methacrylic-based polymer to be produced;
- (2)-2:
- polymerizing the syrup mixture in the plug flow reactor (C) having an inner wall temperature set at the temperature of the complete mixing reactor (A) interior or higher and 230° C. or lower to thereby make a polymerized mixture;
- and
- (2)-3:
- obtaining the second syrup having a content of a polymer in the polymerized mixture of 50 to 90 mass %;
- and
- Step (3):
- feeding the second syrup to a volatile-removing apparatus (E), and continuously separating and removing volatile.
31 more elements
Dependencies are inferred from the claim text.