Classifications

• • 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
  • C08F2/00—Processes of polymerisation
  • C08F2/12—Polymerisation in non-solvents
  • C08F2/16—Aqueous medium
  • C08F2/18—Suspension polymerisation
• • 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
  • C08F14/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
  • C08F14/02—Monomers containing chlorine
  • C08F14/04—Monomers containing two carbon atoms
  • C08F14/06—Vinyl chloride

Definitions

• vinyl dispersion resin refers to polymers and copolymers of vinyl and vinylidene halides, such as vinyl chloride, vinylidene chloride, and the like.
• olefinic mono- mers may be mentioned the ⁇ , ⁇ -olefinically unsaturated carboxylic acids, such as acrylic acid, methacrylic acid, ethacrylic acid, ⁇ -cyanoacrylic acid, and the like; esters of acrylic acid, such as methyl acrylate, ethyl acrylate, butyl acrylate, octyl acrylate, cyano- ethyl acrylate, and the like; esters of methacrylic acid, such as methyl methacrylate, butyl methacrylate, and the like; nitriles, such as acrylonitrile and meth- acrylonitrile; acrylamides, such as methyl acrylamide, N-methylol acrylamide, N-butoxy methacrylamide, and the like; vinyl ethers, such as ethyl vinyl ether, chloro- ethyl vinyl ether, and the like; the vinyl ketones; styrene and
• the present in ⁇ vention is particularly applicable to the manufacture of vinyl dispersion resins cr pastes made by the poly- merization of vinyl chloride or vinylidene chloride alone or in admixture with one or more olefinic mono ⁇ mers copolymerizable therewith in amounts up to about 80% by weight, based on the total weight of the mono ⁇ mers.
• the most preferred vinyl dispersion resin is poly- vinyl chloride (PVC) and the invention, for simplicity and convenience, will be described in connection there- with, it being understood that this is merely intended in an illustrative sense and not limitative. It is to be noted that it has heretofore been proposed to polymerize vinyl monomers in the presence of a plasticizer. See, for example, U.S. Patent No.
• an emulsion polymerization process is " describ ⁇ ed wherein the recipe contains a solvent for the mono ⁇ mer.
• the patent also uses a water-soluble initiator whereas in the present invention a water-insoluble ini- tiator is employed.
• a portion of the water plus emulsifier plus the monomer-dissolv ⁇ ing substance (solvent) are homogenized to form an emulsion.
• the rest of the water plus the monomer or monomer mixture plus the water-soluble initiator are added to the emulsion with ordinary stirring.
• the entire reaction mixture is homo ⁇ genized together and passed to the reactor.
• the important aspect of the present invention is the use in the polymerization recipe of a small amount of water-insoluble plasticizer which allows a re ⁇ duction of up to about 50% or'more in the amount of emulsifier or soap needed in the polymerization recipe.
• the water-insoluble plasticizers there may be named dioctyl adipate, epoxidized soybean oil, , dioctyl phthalate, dioctyl azelate, dicapryl adipate, diisodecyl phthalate, isopropyl myristate, isopropyl palmitate, n-heptyl-n-nonyl adipate, and the like.
• the amount of plasticizer employed is small and generally will be in the range of about 0.05% to about 4.5% by weight, based on the weight of the monomer or monomers being polymerized.
• the amount of plastici- zer will be in the range of about 0.1% to about 1.0% by weight.
• the plasticizer is charged to the premix prior to homogenization along with the other ingredients in usual fashion, with no particular or extraordinary technique being required.
• the aqueous reaction medium will contain one or more emulsifiers or an emulsifier system, such as a salt of a long chain fatty acid and a long straight chain saturated alcohol.
• an alkali metal or ammonium salt of a long chain saturated fatty acid is used as emulsifier or as part of the emulsifier system.
• the saturated fatty acids referred to may be either natural or synthetic and should contain from 8 to 20 carbon atoms.
• such acids there may be named lauric, myristic, palmitic, marganic, stearic, and the like, beef tallow, coconut oil, and the like.
• anionic emulsifiers such as the alkali metal or ammonium salts of the sulfates of alcohols having from 8 to 18 carbon atoms.
• emulsifiers there may be named sodium lauryl sulfate, ethanolamine lauryl sulfate, ethylamine lauryl sulfate, and the like, alkali metal and ammonium salts of sul- fonated petroleum and paraffin oils; sodium salts of hydrocarbon sulfonic acids, such as dodecane-1-sulfonic acid and octadiene-1-sulfonic acid; sodium salts of alpha-olefin sulfonates; aralkyl sulfonates, such as sodium isopropyl benzene sulfonate, sodium dodecyl benzene sulfonate, sodium isobutyl naphthalene sulf
• Nonionic emulsifiers such as octyl- or nonylphenyl polyethoxyethanol, may also be used. Vinyl polymer latices having excellent stability are obtained when employing the alkali metal and ammonium salts of aromatic sulfonic acid, aralkyl sulfonates and long chain sulfonates.
• the emulsifier when using the plasticizer, in accordance with the present invention, is employed in an amount in. the range of about 0.4% to about 4.0% by weight, based on the weight of the monomer or monomers being polymerized. Preferably, the emulsifier is used in an amount in the range of about 0.6% to about 1.2% by weight. When using more than one emulsifier in the system, the com ⁇ bined weight will be in the same range.
• a long straight chain saturated alcohol containing from 8 to 24 carbon atoms is employed in the emulsifier system.
• the addition of the alcohol to the system increases the colloidal sta ⁇ bility of the polymerization system. Further, the pre- sence of the alcohol reduces the amount of polymer buildup and coagulum.
• alcohols there may be named octanol, monanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hex- adecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, heneicosanol, docosanol, tricosanol, tetra- cosanol, etc.
• Mixtures of the alcohols can also be employed.
• a 12 carbon alcohol and an 18 carbon alcohol can be used.
• lower carbon content alcohols can be employed when mixed with the longer chain length alcohols.
• ethoxylated alcohols can be used, such as a mixture of ethoxylated linear primary alcohols containing from 12 to 15 carbon atoms, etc.
• U.S. Patent No. 4,076,920, issued February 28, 1978 there is shown the use of said alcohols with the emulsifier compounds in the emulsifier system.
• the emulsifier is limited to the ammonium salt of the fatty acid and the ratio of alcohol to fatty acid salt can be 1.0 but preferably the ratio is greater than 1.0.
• said ratio of alcohol to emul- sifier* is less than 1.0 and preferably in the range of about 0.15 to about 0.75.
• the same is conducted at a high pH.
• the process can be conducted at a pH in the range of about 2.0 to about 10.5. If the pH is too high it takes too much alkali and if the pH is too low, for example, below 5.0, the coagulum increases.
• the amount of alkaline agent needed to properly adjust and main ⁇ tain the proper pH will depend in part on the particu- lar emulsifier system being used in the reaction mixture.
• the instant process is conducted in the presence of a com ⁇ pound capable of initiating the polymerization reaction.
• Free radical yielding initiators normally used for polymerizing olefinically unsaturated monomers, are satisfactory for use in tne present process. However, it is most important that the initiator be water-in- soluble.
• the useful initiators or catalysts include, for example, the various peroxygen compounds, such as lauryl peroxide, isopropyl peroxydicarbonate, bis(4-tert- butyl cyclohexyl) peroxydicarbonate, di(2-ethyl hexyl) peroxydicarbonate, diisononanoyl peroxide, benzoyl per ⁇ oxide, t-butyl hyrdoperoxide, t-butyl peroxypivalate, cumene hydroperoxide, t-butyl diperphthalate, pelargonyl peroxide, 1-hydroxy cyclohexyl hydrperoxide, tert-butyl peroxyneodecanoate, and the like;
• the initiator is charged completely at the outset of the polymerization. When the initiator is charged at the outset it is added to the monomer pre ⁇ mix with the other ingredients of the reaction mixture. This is particularly true when said premix is homogen ⁇ ized prior to introduction into the reactor.
• the temperature during the premixing and homogenization steps it is necessary that the temperature during the premixing and homogenization steps be kept below the minimum temperature of reactivity of the particu ⁇ lar initiator or initiators being employed.
• the temperature is maintained at 20°C during the mixing step and then during the homogenization step.
• the temperature is then raised to that at which the reaction is to take place.
• An important aspect of the present invention is that the monomer premix should be thoroughly mixed prior to introduction into the reactor.
• the mixing is usually done in a separate vessel, or premix tank.
• the catalyst is added at the beginning of the reaction, it is the last ingredient added to the premix.
• the catalyst being employed is not water- soluble, it should be added to the premix in a suitable solvent therefor which will insure emulsification in the premix and even distribution therein. Needless to say, any such solvent should be inert to the reaction ingredients and reaction conditions. For example, when emp. 1 ying isopropyl peroxydicarbonate as the catalyst or initiator, it is dissolved in hexane and then added to the premix.
• the monomer premix, or reaction premix is thoroughly mixed, it is thereafter subjected to homogenization prior to entering the polymerization step or reactor. It is most important in the present inven- tion that all of the ingredients of the polymerization recipe be homogenized together at the same time. Any convenient means of homogenizing may be employed. It has been found that either a one stage or a two stage Manton—Gaulin h ⁇ mogenizer is a convenient apparatus for homogenizing the premixes contemplated by the present invention. The premix leaves the homogenizer and goes directly into the reaction vessel which preferably con ⁇ tains an inert atmosphere, such as nitrogen.
• an inert atmosphere such as nitrogen.
• the homogenization step is important since it assures the proper particle size of the polymer in the finished latex.
• a particle size in the range of about 0.1 to about 10.0 microns is desirable, with most of the particles being about 2 microns in size.
• the temperature at which the polymerization reaction is conducted is important since the inherent viscosity (IV) of the plastisols made with the vinyl dispersion resins thus produced is a direct function of the temperature of reaction. That is, the higher the temperature the lower the IV. Accordingly, the end use for the vinyl dispersion resin to be produced will normally dictate the polymerization reaction temp ⁇ erature.
• the vinyl dispersion resin is iso- lated in powder form from the latex by means of spray drying. That is, a fine spray of the polymer latex is injected into a heated air chamber thereby removing the water and recovering the dried resin in powder form.
• Plastisols are made with the vinyl dispersion resins of the present invention by uniformly blending or intimately mixing, by conventional means, with 100 parts by weight of the dispersion resin in powder form from about 30 to about 100 parts by weight of one or more plasticizers.
• the useful plasticizers for this purpose may be described as the alkyl and alkoxy alkyl esters of dicarboxylic acids or the esters of a poly- hydric alcohol and monobasic acid.
• dibutyl phthalate dioctyl phthalate, dibutyl sebacate, dinonyl phthalate, di(2- ethylhexyl) phthalate, di(2-ethylhexyl) adipate, dilauryl phthalate, dimetyl tetra-chlorophthalate, butyl phthalyl butyl glycollate, glyceryl stearate, and the like.
• the preferred plasticizers are the liquid di- esters of aliphatic alcohols having from 4 to 20 carbon atoms and dibasic carboxylic acids having from 6 to 14 carbon atoms.
• the plastisols made from the vinyl dispersion resins should have the desired yield. Yield is simply defined as resistance to flow and is normally determined numerically through viscosity measurements employing well known standard techniques. Normally such values are arrived at by calculation from viscosity measurements using a Brookfield Model RVF Viscometer according to ASTM method D1824-61T. Yield is deter ⁇ mined from viscosity measurements of the plastisols at varying r.p.m.'s (revolutions per minute) after initial preparation and intervals of aging. The vis ⁇ cosity is measured in centipoises (cps) at a temperature of 23°C. In the specific examples that follow herein ⁇ after, viscosity measurements were made at 2 rpm.
• the polymer latex or slurry was removed from the reactor and spray-dried to recover the dry PVC or resin. Plastisols were made with the polymer from each run for evaluation purposes.
• the plastisol recipe used, in each case, was as follows: P arts PVC (polyvinyl chloride) 100
• Dissononanoyl peroxide 0.03 - Emulsion'-*-• * - 25 Potassium persulfate — 0.18 ( - • ---The emulsion contained 0.45 part sodium lauryl sulfate; 22.2 parts H 2 0; 0.33 part hexadicane; and 0.67 part dioctyl phthalate. Reaction temperature 55% 50%
• Plastisols were made with the resins in order to de ⁇ termine Brookfield viscosity, density, cell structure rating and color rating.
• the following plastisol recipe was employed and the ingredients mixed in usual manner:
• PVC polyvinyl chloride 100 100 Dioctyl phthalate 72 79.5 Butyl benzyl phthalate 25 27.5 50% disperion of azo-bis- formamide in dioctyl phthala .ttee 66 6 Zinc octoate 3 3
• Example 2 an ethoxylated fatty alcohol was employed and compared to a C, ⁇ + C, g alcohol to show the comparable properties and, as can be seen from the data, improved properties in many respects.
• the polymerizations were carried out as described in Example I and recipes and conditions, along with properties, are given in the table that follows.
• the plastisol recipe was the same as set forth for Run 11 in Example III.
• the many advantages of the present invention are readily ascertainable from the above description and specific examples.
• the vinyl dispersion resins produced, as defined herein, have improved Brookfield viscosity, Severs efflux, better clarity, as well as improved gel temperature and air release. Further, the bloom and bleed properties are improved with the lower emulsifier levels.
• a further important advantage of the present invention is improved plastisol foam properties. Also, the lower emulsifier levels provide a considerable savings in the cost of manufacture thus providing a more economical commercial process.
• An ⁇ other important factor of the present invention is the reduction in polymer buildup in the reactor which not only reduces costs but results in a better quality product being produced with increased yields. Numerous other advantages of the invention will be apparent to those skilled in the art.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Polymerisation Methods In General (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=22351821

Family Applications (1)

Country Status (12)

Cited By (2)

Families Citing this family (4)

Citations (6)

Family Cites Families (1)

• 1980
  • 1980-01-21 US US06/113,840 patent/US4289667A/en not_active Expired - Lifetime
  • 1980-12-19 WO PCT/US1980/001710 patent/WO1981002158A1/en not_active Application Discontinuation
  • 1980-12-19 EP EP81900194A patent/EP0043819B1/en not_active Expired
  • 1980-12-19 BR BR8009021A patent/BR8009021A/pt not_active IP Right Cessation
  • 1980-12-19 DE DE8181900194T patent/DE3069390D1/de not_active Expired
• 1981
  • 1981-01-12 CA CA000368292A patent/CA1191983A/en not_active Expired
  • 1981-01-20 KR KR1019810000152A patent/KR840001828B1/ko active
  • 1981-01-20 IT IT19218/81A patent/IT1135093B/it active
  • 1981-01-20 GR GR63920A patent/GR72991B/el unknown
  • 1981-01-21 ES ES498718A patent/ES8202564A1/es not_active Expired
  • 1981-01-21 IN IN67/CAL/81A patent/IN152264B/en unknown
  • 1981-01-21 MX MX185646A patent/MX156881A/es unknown

Patent Citations (6)

Also Published As

Similar Documents

Legal Events