CA1093733A - Process for preparing polymer resins - Google Patents
Process for preparing polymer resinsInfo
- Publication number
- CA1093733A CA1093733A CA258,158A CA258158A CA1093733A CA 1093733 A CA1093733 A CA 1093733A CA 258158 A CA258158 A CA 258158A CA 1093733 A CA1093733 A CA 1093733A
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- Canada
- Prior art keywords
- polymerization
- rubber
- suspension
- process according
- ethylenic monomer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F291/00—Macromolecular compounds obtained by polymerising monomers on to macromolecular compounds according to more than one of the groups C08F251/00 - C08F289/00
- C08F291/02—Macromolecular compounds obtained by polymerising monomers on to macromolecular compounds according to more than one of the groups C08F251/00 - C08F289/00 on to elastomers
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Graft Or Block Polymers (AREA)
- Polymerisation Methods In General (AREA)
Abstract
Abstract of the Disclosure A process for preparing polymer resins by poly-merization of at least one ethyienic monomer in the presence of at least one rubbery polymer optionally grafted with at least one ethylenic monomer which comprises initiating the polymerization in an emulsion system, adding a suspension stabilizer to the polymerization system after the conversion of the ethylenic monomer reaches 5% by weight and before the emulsion system is broken, and then continuing the polymerization in a suspension system until completion of the polymerization.
By this process, polymer resins can be produced with particles having a beautiful appearance and an even particle size with a narrow range of particle size distribution.
By this process, polymer resins can be produced with particles having a beautiful appearance and an even particle size with a narrow range of particle size distribution.
Description
The present invention relates to a process for preparing polymer resins. More particularly, it relates ~o an improved process for preparing polymer resins by poly-merizing at least one ethylenic rnonomer with at lea~t one rubbery polymer, optionally grafted witil at least one ethylenic monomer.
A process for the production of thermoplastic polymer resins, sucll as ~BS resins (i.e. resins produced from acrylonitrile, butadiene and styrene as the essential monomer components~
and impact resistance polystyrene resins, is known which comprises polymeriziilg at least one ethylenic monomer with at least one rubbery polymer optionally grafted with at least one ethylenic monomer. The polymerization takes place initially in an emulsion system and later in a suspension system, but the emulsified state is not destroyed by the addition of a coagulating agent to the polymerization system before the initiation of the polymerization.
During emulsion polymerization of ethylenic monomers with rubbery polymers in which a polymerization initiator is used, the mixing of the monomer component with the rubber component in the form of a latex results in the solubilization of the latex micelles to a certain extent by reason of absorption of the monomer component therein. However, most of the monomer component forms fine oily droplets, which are dispersed in an aqueous medium in the form of an emulsion. The radicals originating from the polymerization initiator initiate polymerization in the mieelles. While the monomer component in such miscelles is polymerized to form polymers, the micelles are supplied with the monomer component from other micelles or droplets by diEfusion, whereby the micelles become filled Wit}l the resulting polymers. Since, however, an excessive amount of the monomer component is present as oily droplets, the emulsifier protecting the surfaces of the droplets cannot maintain such action, and the emulsion state is destroyed. If a suspension stabilizer is present in the polymerization system at this stage, then the emulsion will be converted to a suspension, and the polymerization will be continued in the resulting suspension system.
Based on the above consideration, various procedures have been proposed for carrying out the polymerization of at least one ethylenic monomer with at least one rubbery polymer, the following being typical: ~1) a procedure wherein the polymerization i6 carried out by the use of a specific poly-merization initiator, the additon of a suspension stabilizer to the polymerization system being made prior to the initiation of polymerization and further when the emulsion state is destroyed ~Japanese Patent Publication No. 21073/1968]; (2) a procedure wherein the polymerization is carried out by the use of another speci~ic polymerization initiator~ the addition of a suspension .stabiliser to the polymerization system being made prior to the initiation of polymerization or when the emulsion state is destroyed [Japanese Patent Publication (unex-amined) No. 56780/1373].
While it is possible to perfect the polymerization initially in the emulsion system and later in the suspension system by the said conventional procedures, much of the resulting polymer is deposited on the walls of the react.ion apparatus and the polyme~r particles have a wide particle size distribution. Further, a large number of small particles of irregular shape are produced in procuedure ~1). In procedure (2~, the addition of stabilizer prior to the initiation of ~polymerization affords the same results as in procedure (1), ~3~3 and additionally, the destruction of the emulsion state results in the production of coarse particles in large propo~tions.
As the result of extensive study to overcome the said drawbacks of the conventional procedures, it has now been Eound that the addition of a suspension stabilizer to the polymeri~ation syste~ at a certain specific stage in the course of the polymeri~ation can result in pa~tlcles of even size a~d beautiful appearance without substantial production of fine and coarse particles and without substantial deposit of the polymer on the walls of the reaction apparatus. The present invention is based on this finding.
According to the present invention, there is provided a process for preparing polymer resins by polymerization of at least one ethylenic monomer in the presenoe of at least one rubbery polymer optionally grafted with at least one ethylenic monomer in such a porportion as to impart a rubber content of 3 to 60 ~ by weight in the resulting resin, which process comprises initiating the polymeriz-ation in an emulsion system, adding a suspension stabil-i7er, in an amount of 0.02 to 1.0 part by weight to 100 parts by weight of water in the polymerization system, to the polymerization system after the conversion of the ethylenic monomer reaches 5% by weight and before the emu]sion system is destroyed, and then continuing the polymerization in a suspension system until completion of the polymerization, the amount of water in the poly-merization system being such as to afford a weight ratio of 1 : 1 - 5 relative to the combined amount of the rubber component and the monomer component and the amount of water at the stage of transference from the emulsion system to the suspension system.
'7~3~
The characteristic feature of this invention is the addition of a suspension stabilizer to the polymeri~ation system at a specific stage during the reaction, i.e. after the conversion of the monomer component reaches 5% by weight and before the emulsion state is destroyed, the addition being made all at once or in portions. When the addition is made prior to this period, polymer partlcles having a wide particle size distribution, and an abnorma] or irregular shape, may be produced in considerable amounts. When the addition is made at or after the destruction of the~emulsion state9 the particles - 4a -~' .
~ ~Q~ ~ 3 become undesirably coarser and so~letimes form aggregative bloc!s. It must be noted, however, that9 the time at which the destruction of the e~ulsion state occurs is associated wi~h the conditions pre~ailing during the polymerization and the emulsion stability of the latex used, etc.
As the suspension stabilizer, any conventional suspension stabilizer may be used, such as fine powders of inorganic compounds sparingly soluble in water (e.g.
magnesium carbonate or calcium tertiary phosphate) or natural or synthetic water-soluble high polymeric materials (e.g. starch, gelatin, partially saponified polyvinyl alchol, polyvinylpyrroli-done, methyl cellulose, hydroxyethyl cellulose or hydroxy-propyl methyl cellulose). These suspension stabilizers may be used alone or in combination. The amount of the suspension stabilizer is usually from 0.02 to 1.0 part by weight to 100 parts by weight of water used in the polymerization sys-tem.
The rubber component to be used in the process of this invention may be a rubbery polymer optionally grafted with at least one ethylenic monomer. Such rubbery polymers are employed in the form of a latex. As the non-grafted rubbery polymer, natural or synthetic rubbery polymers may be used, such as naturai rubber, butadiene rubber, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, isoprene rubber, chloroprene rubber, acrylic rubber, ethylene-propylene-diene terpolymer and ethylene-~inyl acetate copoly-mer. These polymers may be cross-linked or uncrossedlinked. As thegrafted rubbery polymer, polymers obtained by graft polymerizing one or more ethylenic monomers onto any of the afoLesaid natural or synthetic rubbery polymers may be used. These rubbery polymers may be used alone or in combination.
As the monomer component to be polymerized with the rubber component, vinyl mono~ers, vinylidene monomers or vinylene monomers, etc. may be used. More specifically, the following momoners are exemplified: styrenic monomers (e.g.
styrene, ~-methylstyrene, o-ethylstyrene, o-chlorostyrene, p-chlorosLyrene, divinylben~ene), acrylonitrile and its related compounds (e.g. acrylonitrile, ~-chloroacrylonitrile, vinylidene cyanicle), acrylic acid and its esters (e.g. acrylic acid, methyl acrylate, ethyl acrylate), methacrylic acid and its esters ~e.g. methacrylic acid, methyl methacrylate, ethyl metl~acrylate, glycidyl methacrylate), vinyl esters (e.g.
vinyl acetate), vinyl and vinylidene halides (e.g. vinyl chloride, vinylidene chloride), vinyIketone, acrylamide, vinylpyrrolidone, maleic anhydride and maleimide). These monomers may be employed alone or in combination.
The ethylenic monomers may also be used as the monomer components to be grafted onto the natural or synthetic rubbery polymers, as above-mentioned, for the preparation of the grafted rubbery polymer.
With regard to the proportion of the rubber component and the monomer component, there is no particular limitation.
In general, however, il: is preferable to adopt propdrtions which result in the polymer resin having a rubber content of 3 to 60% by weight.
Conventional polymerization initiators and chain transfer agents may be used for polymerization of the monomer component with the rubber component.
As the polymeriæation initiator~ various conventional radical initiators may be used, for instance, organic radical initiators such as azo compounds (e.g. 2,27-azobisiso~utyronitrile9
A process for the production of thermoplastic polymer resins, sucll as ~BS resins (i.e. resins produced from acrylonitrile, butadiene and styrene as the essential monomer components~
and impact resistance polystyrene resins, is known which comprises polymeriziilg at least one ethylenic monomer with at least one rubbery polymer optionally grafted with at least one ethylenic monomer. The polymerization takes place initially in an emulsion system and later in a suspension system, but the emulsified state is not destroyed by the addition of a coagulating agent to the polymerization system before the initiation of the polymerization.
During emulsion polymerization of ethylenic monomers with rubbery polymers in which a polymerization initiator is used, the mixing of the monomer component with the rubber component in the form of a latex results in the solubilization of the latex micelles to a certain extent by reason of absorption of the monomer component therein. However, most of the monomer component forms fine oily droplets, which are dispersed in an aqueous medium in the form of an emulsion. The radicals originating from the polymerization initiator initiate polymerization in the mieelles. While the monomer component in such miscelles is polymerized to form polymers, the micelles are supplied with the monomer component from other micelles or droplets by diEfusion, whereby the micelles become filled Wit}l the resulting polymers. Since, however, an excessive amount of the monomer component is present as oily droplets, the emulsifier protecting the surfaces of the droplets cannot maintain such action, and the emulsion state is destroyed. If a suspension stabilizer is present in the polymerization system at this stage, then the emulsion will be converted to a suspension, and the polymerization will be continued in the resulting suspension system.
Based on the above consideration, various procedures have been proposed for carrying out the polymerization of at least one ethylenic monomer with at least one rubbery polymer, the following being typical: ~1) a procedure wherein the polymerization i6 carried out by the use of a specific poly-merization initiator, the additon of a suspension stabilizer to the polymerization system being made prior to the initiation of polymerization and further when the emulsion state is destroyed ~Japanese Patent Publication No. 21073/1968]; (2) a procedure wherein the polymerization is carried out by the use of another speci~ic polymerization initiator~ the addition of a suspension .stabiliser to the polymerization system being made prior to the initiation of polymerization or when the emulsion state is destroyed [Japanese Patent Publication (unex-amined) No. 56780/1373].
While it is possible to perfect the polymerization initially in the emulsion system and later in the suspension system by the said conventional procedures, much of the resulting polymer is deposited on the walls of the react.ion apparatus and the polyme~r particles have a wide particle size distribution. Further, a large number of small particles of irregular shape are produced in procuedure ~1). In procedure (2~, the addition of stabilizer prior to the initiation of ~polymerization affords the same results as in procedure (1), ~3~3 and additionally, the destruction of the emulsion state results in the production of coarse particles in large propo~tions.
As the result of extensive study to overcome the said drawbacks of the conventional procedures, it has now been Eound that the addition of a suspension stabilizer to the polymeri~ation syste~ at a certain specific stage in the course of the polymeri~ation can result in pa~tlcles of even size a~d beautiful appearance without substantial production of fine and coarse particles and without substantial deposit of the polymer on the walls of the reaction apparatus. The present invention is based on this finding.
According to the present invention, there is provided a process for preparing polymer resins by polymerization of at least one ethylenic monomer in the presenoe of at least one rubbery polymer optionally grafted with at least one ethylenic monomer in such a porportion as to impart a rubber content of 3 to 60 ~ by weight in the resulting resin, which process comprises initiating the polymeriz-ation in an emulsion system, adding a suspension stabil-i7er, in an amount of 0.02 to 1.0 part by weight to 100 parts by weight of water in the polymerization system, to the polymerization system after the conversion of the ethylenic monomer reaches 5% by weight and before the emu]sion system is destroyed, and then continuing the polymerization in a suspension system until completion of the polymerization, the amount of water in the poly-merization system being such as to afford a weight ratio of 1 : 1 - 5 relative to the combined amount of the rubber component and the monomer component and the amount of water at the stage of transference from the emulsion system to the suspension system.
'7~3~
The characteristic feature of this invention is the addition of a suspension stabilizer to the polymeri~ation system at a specific stage during the reaction, i.e. after the conversion of the monomer component reaches 5% by weight and before the emulsion state is destroyed, the addition being made all at once or in portions. When the addition is made prior to this period, polymer partlcles having a wide particle size distribution, and an abnorma] or irregular shape, may be produced in considerable amounts. When the addition is made at or after the destruction of the~emulsion state9 the particles - 4a -~' .
~ ~Q~ ~ 3 become undesirably coarser and so~letimes form aggregative bloc!s. It must be noted, however, that9 the time at which the destruction of the e~ulsion state occurs is associated wi~h the conditions pre~ailing during the polymerization and the emulsion stability of the latex used, etc.
As the suspension stabilizer, any conventional suspension stabilizer may be used, such as fine powders of inorganic compounds sparingly soluble in water (e.g.
magnesium carbonate or calcium tertiary phosphate) or natural or synthetic water-soluble high polymeric materials (e.g. starch, gelatin, partially saponified polyvinyl alchol, polyvinylpyrroli-done, methyl cellulose, hydroxyethyl cellulose or hydroxy-propyl methyl cellulose). These suspension stabilizers may be used alone or in combination. The amount of the suspension stabilizer is usually from 0.02 to 1.0 part by weight to 100 parts by weight of water used in the polymerization sys-tem.
The rubber component to be used in the process of this invention may be a rubbery polymer optionally grafted with at least one ethylenic monomer. Such rubbery polymers are employed in the form of a latex. As the non-grafted rubbery polymer, natural or synthetic rubbery polymers may be used, such as naturai rubber, butadiene rubber, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, isoprene rubber, chloroprene rubber, acrylic rubber, ethylene-propylene-diene terpolymer and ethylene-~inyl acetate copoly-mer. These polymers may be cross-linked or uncrossedlinked. As thegrafted rubbery polymer, polymers obtained by graft polymerizing one or more ethylenic monomers onto any of the afoLesaid natural or synthetic rubbery polymers may be used. These rubbery polymers may be used alone or in combination.
As the monomer component to be polymerized with the rubber component, vinyl mono~ers, vinylidene monomers or vinylene monomers, etc. may be used. More specifically, the following momoners are exemplified: styrenic monomers (e.g.
styrene, ~-methylstyrene, o-ethylstyrene, o-chlorostyrene, p-chlorosLyrene, divinylben~ene), acrylonitrile and its related compounds (e.g. acrylonitrile, ~-chloroacrylonitrile, vinylidene cyanicle), acrylic acid and its esters (e.g. acrylic acid, methyl acrylate, ethyl acrylate), methacrylic acid and its esters ~e.g. methacrylic acid, methyl methacrylate, ethyl metl~acrylate, glycidyl methacrylate), vinyl esters (e.g.
vinyl acetate), vinyl and vinylidene halides (e.g. vinyl chloride, vinylidene chloride), vinyIketone, acrylamide, vinylpyrrolidone, maleic anhydride and maleimide). These monomers may be employed alone or in combination.
The ethylenic monomers may also be used as the monomer components to be grafted onto the natural or synthetic rubbery polymers, as above-mentioned, for the preparation of the grafted rubbery polymer.
With regard to the proportion of the rubber component and the monomer component, there is no particular limitation.
In general, however, il: is preferable to adopt propdrtions which result in the polymer resin having a rubber content of 3 to 60% by weight.
Conventional polymerization initiators and chain transfer agents may be used for polymerization of the monomer component with the rubber component.
As the polymeriæation initiator~ various conventional radical initiators may be used, for instance, organic radical initiators such as azo compounds (e.g. 2,27-azobisiso~utyronitrile9
2,2'-azobisisovaleronitrile, 2,2'-azobis (294 dimethylvalero-nitrile)) and organic peroxides (e.g. diisopropyl peroxydicarbonate, dilauroyl peroxide~ di(3,5~5-trimethylhexanoyl) peroxide~
diben~oyl peroxide, t-butyl peroxy-2-e~hylhexanoate, t-butyl peroxybenzoate, t-butyl peroxylaurate, dicumyl peroxide, t-butyl cumyl peroxide, t-butyl peroxide). These compounds may be used alone or in combination.
As the chain transfer agent, any material having a chain transferring ability may be used. For instance, alkyl halides, alkyl sulfides, al~yl disulfides, l,~,5~8-tetra-hydronaphthalene, terpinolene, thioglycolic esters, ~-methyl-styrene dimer and the like are usable, and alkylmercaptans are especially preferred. The addition of the chain transfer agent to the polymerization system is usually effected all at once or portionwise privr to or in the course of the polymerization.
While there is no particular limitation on the a~ount of water in the polymerization system, it is generally favored to use water in an amount affording a weight ratio of 1:1-5 relative to the combined amount of the rubber component and the monomer component and the amount of water at the stage of the transference from the emulsion system to the suspension system. In most cases, it is desirable to incre~ase the amount of water as the amount of the rubber component is increased.
The particular order in which the ~arious materials, other than the suspension stabilizer, are charged to the reaction apparatus is not particularl~ important. Ilsually, however, it is preferred first to charge a latex of the rubber component into the reaction apparatus contair,ing a desired amount of an aqueous medium9 while stirring, and then to add ~' the remaining materials except the suspension stabilizer thereto.
The polymerization temperature may be appropriately set in view of the decomposition temperature of the pvlymerization initiator, and it is usually bet~een 50 a~d 140C.
Recover~ of the resulting polymer resin from the reaction mixture may be accomplished by a conventional procedure. For instance, the reaction mixture may be filtered to collect particles of the polymer resin, which are then dehydrated and dried.
When desired, conventional additives such as lubricants, plasticiæers, oxidation stabilizers, coloring agents and foaming agents may be incorporated into the polymer resin. Alternatively, these additives may be incorporated into the polymerization system prior to, or in the course of, polymerization.
The polymer resin produced by the process of this invention usually has excellent physical properties, such as high impact resistance. In addition, it is advantageous that the polyme-r resin is obtainable in the form of particles of even shape and size having a good appearance.
Practical and presently preferred embodlments of the present invention are illustratively shown in the following Examples wherein the percentages are by weight.
Example 1 Water (2000 ml) was charged to a glass-lined autoclave having a volume of 5 liters equipped with a turbine type ~
agitating blade and provided with a baffle plate on the internal wall, and ABS latex (pU, 11.1; ABS content, ~0%; ABS
composition, 50% polybutadiene, 15~ acrylonitrile and 35~
styrene with a grafting yield of 50%; average particle size of graft rubber, 0.3 ~) (250 g) was added thereto over a period of 5 minutes while stirring at 600 r.p.m. Then, acrylonitrile ~300 g) and styrene (700 g) were charged to the autoclave over a period of 2 minutes, and a solution of dilauroyl ~3~7~3 peroxide (6.0 g) as a polymerization initiator, tris-nonylphenyl phosphite ~5.0 g) as an oxidation stabilizer and t-dodecylmercaptan (6.0 g) as a chain transfer agent in styrene (50 g) was added thereto. After replacement of the air ;n the autoclave by nitrogen gas, polymerization was initiated by elevation oE
the temperature to 70C and was continued at this temperature For a total period of 5 hours, during which a solution of a 7:3 (by weight) mixture oE partlally saponified poly~inyl alcohol (trade mark "Gosenol G~1-200" manufactured by Nippon Synthetic Chem:ical Industry Co., Ltd.) and hydroxypropyl methyl cellulose (trade mark "Metrose 90 S~1-l00" manufactured by Shin-Rtsu Chemical Industry Co., Ltd.) (2 g) as a suspension stabilizer in water (l00 ml) was added to the polymerization system when the conversion of the monomer component reached 20%.
After the addition of the suspension stabilizer, the emulsion state oE the polymerization system was broken or destroyed and the polymerization system changed to a suspension state, which was stable until completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.35 mm in weight average particle size. The distribution of the particle size was narrow. Only little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was observed.
Examp]e 2 Polymerization was carried out as in Example l, except that the suspension stabilizer was added to the poly~
merization system when the conversion of the monomer component reached 8%.
~3'~3~1 ~fter the addition of the sllspension stabilizer, the emulsion s~ate o~ the polymerization system was hroken and the polymerization system changed to a suspension state, which was stable until completion of the polymerization~
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.32 mm in weight average particle size. The distribution of the particle size was narrow. Only little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was seen.
Example 3 Polymerization was carried out as in Example 1, except that the suspension stabilizer was added to the polymerization system 10 minutes before the breaking of the emulsion state (i.e. when the conversion of the monomer component reached 55%).
Ten minutes after the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the suspension state was formed which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.~;0 mm in weight average particle size. The distribution of the particle size was narrow. Only little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was observed.
Example 4 Polymerization was carried out as in Example 1, except that SBR latex (pH, 12.2; SBR content, 5a%; SeR
diben~oyl peroxide, t-butyl peroxy-2-e~hylhexanoate, t-butyl peroxybenzoate, t-butyl peroxylaurate, dicumyl peroxide, t-butyl cumyl peroxide, t-butyl peroxide). These compounds may be used alone or in combination.
As the chain transfer agent, any material having a chain transferring ability may be used. For instance, alkyl halides, alkyl sulfides, al~yl disulfides, l,~,5~8-tetra-hydronaphthalene, terpinolene, thioglycolic esters, ~-methyl-styrene dimer and the like are usable, and alkylmercaptans are especially preferred. The addition of the chain transfer agent to the polymerization system is usually effected all at once or portionwise privr to or in the course of the polymerization.
While there is no particular limitation on the a~ount of water in the polymerization system, it is generally favored to use water in an amount affording a weight ratio of 1:1-5 relative to the combined amount of the rubber component and the monomer component and the amount of water at the stage of the transference from the emulsion system to the suspension system. In most cases, it is desirable to incre~ase the amount of water as the amount of the rubber component is increased.
The particular order in which the ~arious materials, other than the suspension stabilizer, are charged to the reaction apparatus is not particularl~ important. Ilsually, however, it is preferred first to charge a latex of the rubber component into the reaction apparatus contair,ing a desired amount of an aqueous medium9 while stirring, and then to add ~' the remaining materials except the suspension stabilizer thereto.
The polymerization temperature may be appropriately set in view of the decomposition temperature of the pvlymerization initiator, and it is usually bet~een 50 a~d 140C.
Recover~ of the resulting polymer resin from the reaction mixture may be accomplished by a conventional procedure. For instance, the reaction mixture may be filtered to collect particles of the polymer resin, which are then dehydrated and dried.
When desired, conventional additives such as lubricants, plasticiæers, oxidation stabilizers, coloring agents and foaming agents may be incorporated into the polymer resin. Alternatively, these additives may be incorporated into the polymerization system prior to, or in the course of, polymerization.
The polymer resin produced by the process of this invention usually has excellent physical properties, such as high impact resistance. In addition, it is advantageous that the polyme-r resin is obtainable in the form of particles of even shape and size having a good appearance.
Practical and presently preferred embodlments of the present invention are illustratively shown in the following Examples wherein the percentages are by weight.
Example 1 Water (2000 ml) was charged to a glass-lined autoclave having a volume of 5 liters equipped with a turbine type ~
agitating blade and provided with a baffle plate on the internal wall, and ABS latex (pU, 11.1; ABS content, ~0%; ABS
composition, 50% polybutadiene, 15~ acrylonitrile and 35~
styrene with a grafting yield of 50%; average particle size of graft rubber, 0.3 ~) (250 g) was added thereto over a period of 5 minutes while stirring at 600 r.p.m. Then, acrylonitrile ~300 g) and styrene (700 g) were charged to the autoclave over a period of 2 minutes, and a solution of dilauroyl ~3~7~3 peroxide (6.0 g) as a polymerization initiator, tris-nonylphenyl phosphite ~5.0 g) as an oxidation stabilizer and t-dodecylmercaptan (6.0 g) as a chain transfer agent in styrene (50 g) was added thereto. After replacement of the air ;n the autoclave by nitrogen gas, polymerization was initiated by elevation oE
the temperature to 70C and was continued at this temperature For a total period of 5 hours, during which a solution of a 7:3 (by weight) mixture oE partlally saponified poly~inyl alcohol (trade mark "Gosenol G~1-200" manufactured by Nippon Synthetic Chem:ical Industry Co., Ltd.) and hydroxypropyl methyl cellulose (trade mark "Metrose 90 S~1-l00" manufactured by Shin-Rtsu Chemical Industry Co., Ltd.) (2 g) as a suspension stabilizer in water (l00 ml) was added to the polymerization system when the conversion of the monomer component reached 20%.
After the addition of the suspension stabilizer, the emulsion state oE the polymerization system was broken or destroyed and the polymerization system changed to a suspension state, which was stable until completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.35 mm in weight average particle size. The distribution of the particle size was narrow. Only little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was observed.
Examp]e 2 Polymerization was carried out as in Example l, except that the suspension stabilizer was added to the poly~
merization system when the conversion of the monomer component reached 8%.
~3'~3~1 ~fter the addition of the sllspension stabilizer, the emulsion s~ate o~ the polymerization system was hroken and the polymerization system changed to a suspension state, which was stable until completion of the polymerization~
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.32 mm in weight average particle size. The distribution of the particle size was narrow. Only little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was seen.
Example 3 Polymerization was carried out as in Example 1, except that the suspension stabilizer was added to the polymerization system 10 minutes before the breaking of the emulsion state (i.e. when the conversion of the monomer component reached 55%).
Ten minutes after the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the suspension state was formed which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.~;0 mm in weight average particle size. The distribution of the particle size was narrow. Only little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was observed.
Example 4 Polymerization was carried out as in Example 1, except that SBR latex (pH, 12.2; SBR content, 5a%; SeR
3~
composition, 90% polybutadiene and 10~ styrene) (200 g) was used in plae of the ~BS latex.
~fter the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and thP polymerization system changed ~o the suspensLon state, which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.35 mm in weight average particle size. The distribution of the particle size was narrow.
Example 5 Polymerization was carried out as in Example 1, except that SBR latex as employed in Example 4 (60 g) was used in addition to and together with the ABS latex.
After the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the polymerization system changed to a suspension state, which was stable until the completion oE the polymerization.
The polymer resin thus produced was recovered ~rom the reaction mixture by filtration, and was dehydrat~d and dried to give spherical particles of 0.40 mm in weight average particle size. The distribution of the particle size was narrow.
Example ~
Water (2500 ml) and the S~ latex employed in Example 4 (400 g) were charged to an autoclave as employed in Example 1, and stirring was started at 600 r.p.m. Then, styrene (1000 g) was added to the autoclave over a period of 3 minutes, and a solutlon of t-butyl peroxybenzoate (5.0 g) as a polymerlzation initiator, t~dodecylmercaptan (1.0 g) as a chain transfer .
agen~ and tris-nonylphenyl phosphite (5.0 g) as an oxidation stabilizer in styrene (50 g) was added thereto. After replace-ment of the air in the autoclave by nitrogen gas, poly-merization was initiated by elevation of the temperature to 115C and was continued at this temperat~re for a total period of 4 hours, during which a solution of methyl cellulose (trade mark "Marpolose M-4000" manufactured by Matsomoto Yushi Seiyaku Co., Ltd.) (4.0 g) as a suspension stabilizer in water (100 ml) was added to the polymerization system when the conversion of the monomer component reached 25~.
After the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the polymerization system changed to a suspension st~te, which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0~40 mm in weight average particle size. The distribution of the particle size was narrow. ~nly little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walIs of the autoclave was observed.
Example 7 Water (2500 ml) and the SBR latex employed in Example ~ (350 g) were charged to an autoclave as employed in Example 1, and stirring was started at 600 r.p~. Then, styrene (300 g) and methyl methacrylate (700 g) were added to the autoclave over a period of 5 minutes, and a solution of dilauroyl peroxide (8.0 g) as a polymerization initiator, t-dodecylmercaptan {3.0 g) as a chain transfer agent and tris-nonylphenyl phosphite (5.0 g) as an ~oxidation stabilizer in styrene (50 g) was ad~ded thereto. After replacement of the D3t`~3 air in the autoclave by nitrogen gas, polymerization ~7as initiated by elevation of the temperature to 70 C and was continued at this temperature for a total period of 5 hours, during which the suspension stabilizer employed in Example ]
was added to the polymerization system when the conversion of the monomer reached 15%.
After the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the polymerization system changed to a suspension state, which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried ~o give spherical particles of 0.35 mm in weight average particle size. The distribution of the particle siæe was narrow. Only little turbidity was reco~nized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was observed.
_omparative Exam~le l Polymerization was carried out as in Example 1, except that the addition of the suspension stabilizer to the polymerization system was effected prior to the initiation of the polymerization. In the course of polymeriza~ion, the emulsion state of the polymerization system was broken and the system was changed to a suspension state.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give fine particles of 0.30 mm in weight average particle size. The distribution of the particle size was broad and inclined to the side of finer particles~ Considerable turbidity was found in the filtrate and a large deposit of the polymer on the wails of the autoclave was observed.
3'733 Comparative ~xamp~e 2 Polymerization was carried out as in Examp~e 1, except that the addition of the suspension stabilizer to the polymerization system was effected at the breaking of the emulsion state.
Tlle polymerization resin thus procluced was recovered rom the reaction mixture by filtration, and was dehydrated and dried to give coarse particles of 1.52 mm in weight average particle size and of irregular form. The distribution of the particle 9ize was broad and inclined to the coarser particle size. A large deposit of the polymer on the walls of the autoclave was observed.
Comparative Example 3 Polymerization was carLied out as in Example 1, except that the addition of the suspension stabilizer to the polymerization system was effected 30 minutes after the change of the emulsion state of the polymerization system to a suspension state (i.e. when the conversion of the monomer component reached 70 %). The polymer particles thus produced were aggregated into blocks 9 and the polymerization could not be completed.
Comparative Example 4 Polymerization was carried out as in Example 6 9 except that the addition of the suspension stabilizer to the polymerization system was effected before the initiation of the polymerization or at the breaking of the emulsion state.
As a result, fine particles of 0.31 ~m in weight average particle size with a broad distribution were obtained in the former case and coarse particles of 1.50 mm in weight average particle size with a broad distribution were obtained in the la~ter case. In both cases, a large deposit of the 3~3~
polymer on the walls of the autoclave was cbserved. Further, in the former case, remarkable turbidity was fourld in the filtrate.
mparative Example ~
Polymerization was carried out as in Example 7, except that the addition of the suspension stabilizer to the polymerization system was effected before the initiation of the polymerization or at the breaking of the emulsion state.
As a result, fine particles of 0.30 mm in weight average particle size with a broad distribution were obtained in the former case and coarse particles of 1.53 mm in weight average particle size with a broad distribution were obtained in the latter case. In both cases, a large deposit of the polymer on the wall of the autoclave was observed. Further, in the former case, remarkable turbidity was found in the filtrated.
composition, 90% polybutadiene and 10~ styrene) (200 g) was used in plae of the ~BS latex.
~fter the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and thP polymerization system changed ~o the suspensLon state, which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0.35 mm in weight average particle size. The distribution of the particle size was narrow.
Example 5 Polymerization was carried out as in Example 1, except that SBR latex as employed in Example 4 (60 g) was used in addition to and together with the ABS latex.
After the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the polymerization system changed to a suspension state, which was stable until the completion oE the polymerization.
The polymer resin thus produced was recovered ~rom the reaction mixture by filtration, and was dehydrat~d and dried to give spherical particles of 0.40 mm in weight average particle size. The distribution of the particle size was narrow.
Example ~
Water (2500 ml) and the S~ latex employed in Example 4 (400 g) were charged to an autoclave as employed in Example 1, and stirring was started at 600 r.p.m. Then, styrene (1000 g) was added to the autoclave over a period of 3 minutes, and a solutlon of t-butyl peroxybenzoate (5.0 g) as a polymerlzation initiator, t~dodecylmercaptan (1.0 g) as a chain transfer .
agen~ and tris-nonylphenyl phosphite (5.0 g) as an oxidation stabilizer in styrene (50 g) was added thereto. After replace-ment of the air in the autoclave by nitrogen gas, poly-merization was initiated by elevation of the temperature to 115C and was continued at this temperat~re for a total period of 4 hours, during which a solution of methyl cellulose (trade mark "Marpolose M-4000" manufactured by Matsomoto Yushi Seiyaku Co., Ltd.) (4.0 g) as a suspension stabilizer in water (100 ml) was added to the polymerization system when the conversion of the monomer component reached 25~.
After the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the polymerization system changed to a suspension st~te, which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give spherical particles of 0~40 mm in weight average particle size. The distribution of the particle size was narrow. ~nly little turbidity was recognized in the filtrate.
No substantial deposit of the polymer on the walIs of the autoclave was observed.
Example 7 Water (2500 ml) and the SBR latex employed in Example ~ (350 g) were charged to an autoclave as employed in Example 1, and stirring was started at 600 r.p~. Then, styrene (300 g) and methyl methacrylate (700 g) were added to the autoclave over a period of 5 minutes, and a solution of dilauroyl peroxide (8.0 g) as a polymerization initiator, t-dodecylmercaptan {3.0 g) as a chain transfer agent and tris-nonylphenyl phosphite (5.0 g) as an ~oxidation stabilizer in styrene (50 g) was ad~ded thereto. After replacement of the D3t`~3 air in the autoclave by nitrogen gas, polymerization ~7as initiated by elevation of the temperature to 70 C and was continued at this temperature for a total period of 5 hours, during which the suspension stabilizer employed in Example ]
was added to the polymerization system when the conversion of the monomer reached 15%.
After the addition of the suspension stabilizer, the emulsion state of the polymerization system was broken and the polymerization system changed to a suspension state, which was stable until the completion of the polymerization.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried ~o give spherical particles of 0.35 mm in weight average particle size. The distribution of the particle siæe was narrow. Only little turbidity was reco~nized in the filtrate.
No substantial deposit of the polymer on the walls of the autoclave was observed.
_omparative Exam~le l Polymerization was carried out as in Example 1, except that the addition of the suspension stabilizer to the polymerization system was effected prior to the initiation of the polymerization. In the course of polymeriza~ion, the emulsion state of the polymerization system was broken and the system was changed to a suspension state.
The polymer resin thus produced was recovered from the reaction mixture by filtration, and was dehydrated and dried to give fine particles of 0.30 mm in weight average particle size. The distribution of the particle size was broad and inclined to the side of finer particles~ Considerable turbidity was found in the filtrate and a large deposit of the polymer on the wails of the autoclave was observed.
3'733 Comparative ~xamp~e 2 Polymerization was carried out as in Examp~e 1, except that the addition of the suspension stabilizer to the polymerization system was effected at the breaking of the emulsion state.
Tlle polymerization resin thus procluced was recovered rom the reaction mixture by filtration, and was dehydrated and dried to give coarse particles of 1.52 mm in weight average particle size and of irregular form. The distribution of the particle 9ize was broad and inclined to the coarser particle size. A large deposit of the polymer on the walls of the autoclave was observed.
Comparative Example 3 Polymerization was carLied out as in Example 1, except that the addition of the suspension stabilizer to the polymerization system was effected 30 minutes after the change of the emulsion state of the polymerization system to a suspension state (i.e. when the conversion of the monomer component reached 70 %). The polymer particles thus produced were aggregated into blocks 9 and the polymerization could not be completed.
Comparative Example 4 Polymerization was carried out as in Example 6 9 except that the addition of the suspension stabilizer to the polymerization system was effected before the initiation of the polymerization or at the breaking of the emulsion state.
As a result, fine particles of 0.31 ~m in weight average particle size with a broad distribution were obtained in the former case and coarse particles of 1.50 mm in weight average particle size with a broad distribution were obtained in the la~ter case. In both cases, a large deposit of the 3~3~
polymer on the walls of the autoclave was cbserved. Further, in the former case, remarkable turbidity was fourld in the filtrate.
mparative Example ~
Polymerization was carried out as in Example 7, except that the addition of the suspension stabilizer to the polymerization system was effected before the initiation of the polymerization or at the breaking of the emulsion state.
As a result, fine particles of 0.30 mm in weight average particle size with a broad distribution were obtained in the former case and coarse particles of 1.53 mm in weight average particle size with a broad distribution were obtained in the latter case. In both cases, a large deposit of the polymer on the wall of the autoclave was observed. Further, in the former case, remarkable turbidity was found in the filtrated.
Claims (8)
1. A process for preparing polymer resins by polymerization of at least one ethylenic monomer in the presence of at least one rubbery polymer optionally grafted with at least one ethylenic monomer in such a porportion as to impart a rubber content of 3 to 60 % by weight in the resulting resin, which process comprises initiating the polymerization in an emulsion system, adding a suspension stabilizer, in an amount of 0.02 to 1.0 part by weight to 100 parts by weight of water in the polymerization system, to the polymerization system after the conversion of the ethylenic monomer reaches 5% by weight and before the emulsion system is destroyed, and then continuing the polymerization in a suspension system until completion of the polymerization, the amount of water in the polymerization system being such as to afford a weight ratio of 1 : 1 - 5 relative to the combined amount of the rubber component and the monomer component and the amount of water at the stage of transference from the emulsion system to the suspension system.
2. A process according to claim 1, wherein the suspension stabilizer is selected from fine powders of inorganic compounds sparingly soluble in water and natural or synthetic water-soluble high polymeric materials.
3. A process according to claim 2, wherein the suspension stabilizer is selected from magnesium carbonate, calcium tertiary phosphate, starch, gelatin, partially saponified polyvinyl alcohol, polyvinylpyrrolidone, methyl cellulose, hydroxyethyl cellulose and hydroxypropyl methyl cellulose.
4. A process according to claim 1, wherein the rubbery polymer optionally grafted with at least one ethylenic monomer is selected from natural rubber, butadiene rubber, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, isoprene rubber, chloroprene rubber, acrylic rubber, ethylene-propylene-diene terpolymer and ethylene-vinyl acetate copolymer and their graft copolymers with at least one of styrenic monomers, acrylonitrile and its related compounds, acrylic acid and its esters, methacrylic acid and its esters, vinyl esters, vinyl and vinylidene halides, vinylketone, acrylamide, vinylpyrrolidone, maleic anhydride and maleimide.
5. A process according to claim 1, wherein the ethylenic monomer to be polymerized in the presence of the rubbery polymer optionally grafted with at least one ethylenic monomer is selected from styrenic monomers, acrylonitrile and its related compounds, acrylic acid and its esters, methacrylic acid and its esters, vinyl esters, vinyl and vinylidene halides, vinylketone, acrylamide, vinylpyrrolidone, maleic anhydride and maleimide.
6. A process according to claim 1, wherein the polymerization is carried out in the presence of a polymerization initiator.
7. A process according to claim 1, wherein the polymerization is carried out in the presence of a chain transfer agent.
8. A process according to claim 1, wherein the polymerization is carried out at a temperature from 50 to 140°C.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9405375A JPS5217593A (en) | 1975-07-31 | 1975-07-31 | Process for producing high-impact resins |
| JP94053/1975 | 1975-07-31 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1093733A true CA1093733A (en) | 1981-01-13 |
Family
ID=14099794
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA258,158A Expired CA1093733A (en) | 1975-07-31 | 1976-07-30 | Process for preparing polymer resins |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5217593A (en) |
| CA (1) | CA1093733A (en) |
| DE (1) | DE2634393B2 (en) |
| FR (1) | FR2319651A1 (en) |
| GB (1) | GB1525824A (en) |
| NL (1) | NL160295C (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2397431A1 (en) * | 1977-07-12 | 1979-02-09 | Ugine Kuhlmann | PROCESS FOR MANUFACTURING COPOLYMERS GRAFT BY POLYMERIZATION-GRAFTING IN EMULSION-SUSPENSION |
| DE2811549A1 (en) * | 1978-03-16 | 1979-09-20 | Bayer Ag | Graft copolymers containing (meth) acrylic acid or (meth) acrylic acid esters |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3436440A (en) * | 1964-05-14 | 1969-04-01 | Hitachi Chemical Co Ltd | Method of graft-copolymerization of monomers onto diene-type polymer |
| US3887652A (en) * | 1970-11-09 | 1975-06-03 | Dart Ind Inc | Process for producing transparent graft polymer compositions |
-
1975
- 1975-07-31 JP JP9405375A patent/JPS5217593A/en active Granted
-
1976
- 1976-07-30 CA CA258,158A patent/CA1093733A/en not_active Expired
- 1976-07-30 GB GB3188576A patent/GB1525824A/en not_active Expired
- 1976-07-30 DE DE19762634393 patent/DE2634393B2/en not_active Withdrawn
- 1976-07-30 FR FR7623488A patent/FR2319651A1/en active Granted
- 1976-08-02 NL NL7608594A patent/NL160295C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| NL160295B (en) | 1979-05-15 |
| GB1525824A (en) | 1978-09-20 |
| JPS5217593A (en) | 1977-02-09 |
| FR2319651A1 (en) | 1977-02-25 |
| DE2634393A1 (en) | 1977-02-03 |
| JPS5533768B2 (en) | 1980-09-02 |
| NL7608594A (en) | 1977-02-02 |
| DE2634393B2 (en) | 1981-02-19 |
| FR2319651B1 (en) | 1979-08-10 |
| NL160295C (en) | 1979-10-15 |
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