CN103755858B

CN103755858B - A kind of solution polymerization process of polyvinylidene fluoride copolymer

Info

Publication number: CN103755858B
Application number: CN201310745969.7A
Authority: CN
Inventors: 王汉利; 李秀芬; 唐妮; 王军
Original assignee: Shandong Dongyue Shenzhou New Material Co Ltd
Current assignee: Shandong Dongyue Shenzhou New Material Co Ltd
Priority date: 2013-12-30
Filing date: 2013-12-30
Publication date: 2016-04-27
Anticipated expiration: 2033-12-30
Also published as: CN103755858A

Abstract

The present invention relates to a kind of preparation method of polyvinylidene fluoride copolymer.This polymerization polymerization process used is novel solutions polymerization, and employing initial monomer is dispersion medium, and organo-peroxide class is initiator, and ketone and ester class are molecular weight regulator, this process polymerisation mild condition, and technique is simple, easy to operate, and cost is low; Its product impurity content is few, and thermo-chemical stability is good, and the low heat decomposition temperature of fusing point is high, and processing temperature is wide easy to operate; Snappiness is good, not easy to crack.

Description

A kind of solution polymerization process of polyvinylidene fluoride copolymer

Technical field

The invention belongs to technical field of macromolecules, be specifically related to a kind of solution polymerization process of polyvinylidene fluoride copolymer.

Background technology

Polyvinylidene difluoride (PVDF) (PVDF) has good heat-resisting, uvioresistant that corrosion resistance nature, good chemical stability are good, excellent and ageing-resistant performance, the working method such as mold pressing and injection moulding can be adopted to produce PVDF pump, valve, tube fittings and filler etc., adopt Extrusion processes can produce PVDF rod, plate, pipe, flexible pipe, monofilament and electric wire insulation layer etc., purposes widely.PVDF multipolymer, compared with homopolymer, has the advantages such as fusing point is low, snappiness good, easy processing, so polyvinylidene fluoride copolymer is more and more subject to people's favor.

Polymerization technique aspect, traditional PVDF polymerization technique is adopt letex polymerization and suspension polymerization mostly, and they need to add emulsifying agent, makes system keep stable, is removed by auxiliary agent at the end of polymerization by washing again.Although by the removing of emulsifying agent major part, complete Ex-all can be difficult to by technological processs such as washings.The emulsifying agent contained can affect the thermal stability of polymkeric substance, simultaneously also can increase its cost adding of emulsifying agent, increases the complicacy of technique, patent US2007290407 US7045584 CN107164A etc. all adopt this technique.

Next also has partial monopoly to be adopt solution polymerization, but the solvent that they adopt is fluorine-containing alkane, and that fluorine-containing alkane has because be prohibited to the having destruction of ozonosphere, as F113, some price comparisons are expensive, as patent CN101508749A.For this situation, the present invention adopt R 1216 and vinylidene initial monomeric mixture be reaction medium to prepare polyvinylidene fluoride copolymer, reaction terminate after, this mixture can recycling.This method avoids suspension polymerization and letex polymerization must add expensive auxiliary agent and the shortcoming of the washing process of complexity, avoid solution polymerization adopt fluorine-containing alkane to be the trouble of reaction medium.This technological operation is simple, low cost of manufacture, and to environment low stain, the polyvinylidene fluoride copolymer of preparation has good flexility, has good thermostability and good degree of cleaning, may be used for the high-end fields such as aerospace.

Summary of the invention

The invention describes the solution polymerization process of a kind of low cost, less energy-consumption, low stain, high-performance poly vinylidene fluoride copolymers.

The solution polymerization process of polyvinylidene fluoride copolymer of the present invention, the reaction medium of use is R 1216 and vinylidene initial monomeric mixture, and initiator is peroxy dicarbonates, and molecular weight regulator is ester class or ketone.

The mol ratio of R 1216 and vinylidene is: 1: 1.5 ~ 20.

Ester class is ethyl propionate, and ketone is acetone.

Comprise the following steps:

(1) add in reactor by initial monomeric mixture, heating, adds initiator and molecular weight regulator, and heat-insulation pressure keeping is polymerized;

(2) keep temperature in the kettle, add and add initial monomeric mixture, pressure is remained in the level of step (1), adds molecular weight regulator simultaneously;

(3) cool, take out obtained multipolymer, drying-granulating, packaging;

Described initial monomeric mixture be R 1216 and vinylidene in molar ratio 1: 1.5 ~ 5 mixing;

Described add monomer mixture be R 1216 and vinylidene in molar ratio 1: 6 ~ 20 mixing.

In step (1), the mol ratio of initial monomeric mixture, initiator and molecular weight regulator is: 100: 0.01 ~ 0.2: 0.01 ~ 0.5.

Polymeric reaction temperature in step (1) and step (2) is 30 ~ 120 DEG C, and pressure is 0.5 ~ 4.5MPa.

Polymeric reaction temperature in step (1) and step (2) is 40 ~ 60 DEG C, and pressure is 0.8 ~ 1.2MPa.

The mass ratio added monomer mixture and add molecular weight regulator added in step (2) is 50: 1.

Drying temperature is 80 ~ 100 DEG C, and the time is 10 ~ 12h.

Compared with prior art, the present invention has following beneficial effect:

Production technique is simple, production cost is low, environmental pollution is few and this polymerization product snappiness is good, Heat stability is good, good processability.

Embodiment

Below in conjunction with embodiment, the present invention is described further.

Embodiment 1

For the polymeric kettle of 5L, find time, deoxygenation, after oxygen level is qualified, by reactor cooling to 0 DEG C, add the initial monomeric mixture of 15kg, initial monomeric mixture is the mol ratio of R 1216 and vinylidene is the mixing of 1: 5, and reactor is heated to 50 DEG C, now pressure is 0.9 ± 0.1MPa, adds peroxy dicarbonate two (3-methoxybutyl) initiator and the 5g acetone of 300g1.0wt%.Reaction starts, add to reactor and add monomer mixture, keep constant pressure, when adding 250g and adding monomer mixture, then add 5g molecular weight regulator acetone, when adding the heating of stopped reaction device when 500g adds monomer mixture, stop adding monomer mixture, stop stirring, reaction mass is cooled to 10 DEG C, unreacted monomer is collected copolyreaction after being used as in withdrawing can, add monomer mixture be R 1216 and vinylidene in molar ratio 1: 6 mixing.Emptying, draws off obtained multipolymer, and with the vacuum drying oven of 80 DEG C in heat 10h to remove remaining initiator and solvent.Then by multipolymer granulation, packaging.

Embodiment 2

For the polymeric kettle of 5L, find time, deoxygenation, after oxygen level is qualified, by reactor cooling to 10 DEG C, add the initial monomeric mixture of 15kg, initial monomeric mixture is the mol ratio of R 1216 and vinylidene is the mixing of 1: 3, and reactor is heated to 55 DEG C, now pressure is 1.0 ± 0.1Mpa, adds peroxy dicarbonate two (3-methoxybutyl) initiator and the 5g ethyl propionate of 300g1.0wt%.Reaction starts, add to reactor and add monomer mixture, keep constant pressure, when adding 250g and adding monomer mixture, add 5g molecular weight regulator ethyl propionate again, when adding after 500g adds monomer mixture, the heating of stopped reaction device, stop adding monomer mixture, stop stirring, reaction mass is cooled to 30 DEG C, unreacted monomer is collected copolyreaction after being used as in withdrawing can, add monomer mixture be R 1216 and vinylidene in molar ratio 1: 20 mixing.Emptying, draws off obtained multipolymer, and with the vacuum drying oven of 100 DEG C in heat 12h to remove remaining initiator and solvent.Then by multipolymer granulation, packaging.

Embodiment 3

For the polymeric kettle of 5L, find time, deoxygenation, after oxygen level is qualified, by reactor cooling to 5 DEG C, add the initial monomeric mixture of 15kg, initial monomeric mixture is the mol ratio of R 1216 and vinylidene is the mixing of 1: 1.5, and reactor is heated to 60 DEG C, now pressure is 1.1 ± 0.1Mpa, adds Diisopropyl azodicarboxylate initiator and the 5g acetone of 300g1.0wt%.Reaction starts, add to reactor and add monomer mixture, keep constant pressure, when adding 250g and adding monomer mixture, then add 5g molecular weight regulator acetone, when adding the heating of stopped reaction device when 500g adds monomer mixture, stop adding monomer mixture, stop stirring, reaction mass is cooled to 20 DEG C, unreacted monomer is collected copolyreaction after being used as in withdrawing can, add monomer mixture be R 1216 and vinylidene in molar ratio 1: 15 mixing.Emptying, draws off obtained multipolymer, and with the vacuum drying oven of 90 DEG C in heat 10-12h to remove remaining initiator and solvent.Then by multipolymer granulation, packaging.

Comparative example 1

For the polymeric kettle of 5L, in the polymeric kettle cleaned, add 3.5kg deionized water, 15g30% perfluoro ammonium caprylate solution, 20g paraffin, find time, deoxygenation, be qualified to oxygen level≤20ppm, then polymeric kettle is heated up and add initial monomer 110g simultaneously, initial monomeric mixture is the mol ratio of R 1216 and vinylidene is the mixing of 1: 5, the still temperature of still to be polymerized reaches 60 DEG C, after still pressure reaches 3.0MPa, the concentration squeezing into 300g is fast peroxy dicarbonate two (3-methoxybutyl) aqueous solution and the 5g acetone of 1.0%, start polyreaction, add to reactor and add monomer mixture, keep constant pressure, when adding 250g and adding monomer mixture, add 5g molecular weight regulator acetone again, when adding the heating of stopped reaction device when 500g adds monomer mixture, stop adding monomer mixture, stop stirring, stopped reaction, add monomer mixture be R 1216 and vinylidene in molar ratio 1: 10 mixing.Reclaim unreacted monomer, emulsion carry out condensing, wash, dry, granulation, test packing.

Comparative example 2

For the polymeric kettle of 5L, in the polymeric kettle cleaned, add 3.5kg deionized water, find time, deoxygenation, be qualified to oxygen level≤20ppm, then initial monomer 110g is added simultaneously to polymerization kettle temperature raising, initial monomeric mixture is the mol ratio of R 1216 and vinylidene is the mixing of 1: 4, the still temperature of still to be polymerized reaches 60 DEG C, after still pressure reaches 3.0MPa, with peroxy dicarbonate two (3-methoxybutyl) aqueous solution and 5g acetone that the concentration that volume pump squeezes into 300g is fast 1.0%, start polyreaction, add to reactor and add monomer mixture, keep constant pressure, when adding 250g and adding monomer mixture, add 5g molecular weight regulator acetone again, when adding 500g and adding monomer mixture, the heating of stopped reaction device, stop adding monomer mixture, stop stirring, stopped reaction, add monomer mixture be R 1216 and vinylidene in molar ratio 1: 13 mixing.Reclaim unreacted monomer, filtration, washing, oven dry, granulation, test packing.

This example of comparative example 3(is homopolymer)

For the polymeric kettle of 5L, in the polymeric kettle cleaned, add 3.5kg deionized water, 15g30% perfluoro ammonium caprylate solution, 20g paraffin, find time, deoxygenation, be qualified to oxygen level≤20ppm, then polymeric kettle is heated up and add initial vinylidene fluoride monomers 110g simultaneously, the still temperature of still to be polymerized reaches 60 DEG C, after still pressure reaches 3.0MPa, the concentration squeezing into 300g is fast peroxy dicarbonate two (3-methoxybutyl) aqueous solution and the 5g acetone of 1.0%, start polyreaction, add to reactor and add vinylidene fluoride monomers, keep constant pressure, when adding 250g and adding monomer, add 5g molecular weight regulator acetone again, when adding the heating of stopped reaction device when 500g adds monomer, stop adding vinylidene fluoride monomers, stop stirring, stopped reaction.Reclaim unreacted monomer, emulsion carry out condensing, wash, dry, granulation, test packing.

Embodiment 1,2,3 is compared with comparative example 1,2, and technique is simple, and easy to operate, cost is low, and degree of cleaning are high; Compared with comparative example 3, product snappiness is good, and the low workability of fusing point can be good

The product performance of above-mentioned each example are shown in table 1.

Table 1PVDF performance comparison

Claims

1. a solution polymerization process for polyvinylidene fluoride copolymer, is characterized in that, the comonomer of employing is the mixing of R 1216 and vinylidene, and initiator is peroxy dicarbonates, and molecular weight regulator is ester class or ketone;

Comprise the following steps: initial monomeric mixture adds in reactor by (1), heating, adds initiator and molecular weight regulator, and heat-insulation pressure keeping is polymerized; (2) keep temperature in the kettle, add and add monomer mixture, pressure is remained in the level of step (1), adds molecular weight regulator simultaneously; (3) cool, take out obtained multipolymer, drying-granulating, packaging; Described initial monomeric mixture be R 1216 and vinylidene in molar ratio 1: 1.5 ~ 5 mixing; Described add monomer mixture be R 1216 and vinylidene in molar ratio 1: 6 ~ 20 mixing;

2. the solution polymerization process of polyvinylidene fluoride copolymer according to claim 1, is characterized in that, described ester class is ethyl propionate, and ketone is acetone.

3. the solution polymerization process of polyvinylidene fluoride copolymer according to claim 1, is characterized in that, in step (1), the mol ratio of initial monomeric mixture, initiator and molecular weight regulator is: 100: 0.01 ~ 0.2: 0.01 ~ 0.5.

4. the solution polymerization process of polyvinylidene fluoride copolymer according to claim 1, is characterized in that, the mass ratio adding the molecular weight regulator of monomer mixture and interpolation added in step (2) is 50: 1.

5. the solution polymerization process of polyvinylidene fluoride copolymer according to claim 1, is characterized in that, drying temperature is 80 ~ 100 DEG C, and the time is 10 ~ 12h.