DE2701680A1 - IMPROVED PROCESS FOR THE PREPARATION OF VINYL HALOGENIDE POLYMERS AND COPOLYMERS WITH POLYOLEFINS - Google Patents

Description

Patent attorneys Dipl.-Ing. H. Wkickmann, Dipl.-Phys. Dr. K. Fincke HWEMY Dipl.-Ing. F. A. Veickmann, Dipl.-Chem. B. Huber

Case 3877 ^{8 MUNICH 86} > ^DEN

POST BOX 860 «20

MÖHLSTRASSE 22, CALL NUMBER 98 3921/22

HOOKER CHEMICALS & PLASTICS CORP. Niagara Falls, New York, 14302, V.St.A.

Improved Process for Making Vinyl Halide Polymers and copolymers with polyolefins

Polymers with very good impact resistance, reduced particle size and increased proportions of powdery material v / earth obtained in the bulk polymerization of a vinyl halide or its mixture with one or more comonomers in the presence of a polyolefin of high molecular weight, which to the polymerization mass after conversion from 0 to about 20 wt. SS monomer (s) is added to the polymer, removal from the polymerization mass during its thick paste state of sufficient vinyl halide to adjust the effective concentration of the polyolefin to about 3.5 percent based on the vinyl halide. The resulting product, which contains an increased proportion of fine or powdery material and which does not contain any massive agglomerates, requires less mechanical work during comminution or shorter heating times during melting in the subsequent known processing stages.

The invention relates to an improved process for preparing polymers having high impact strength and comparable

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better processability. More particularly, the invention relates to improvements in the bulk polymerization of vinyl halide or vinyl halide comonomer mixtures in the presence of high concentrations of high molecular weight polyolefins. In particular, it relates to a new improvement in this polymerization, which causes the formation of product agglomerates is avoided and a more finely divided, more homogeneous and easier to process or treat, particulate polymer or solid particle polymer obtained will.

The polymerization of vinyl halides such as vinyl chloride, or up to about 50 wt.% Of its mixture with a compatible comonomer in the composition in the presence of a polyolefin to produce a vinyl halide polymers with improved impact strength and processability is known. According to U.S. Patent Application Serial No. 674,202, filed April 5, 1976 by A. Takahashi, which is a continuetion-in-part application of U.S. Application Serial No. 427,895, filed December 26, 1973 which in turn is a continuation-in-part application of U.S. Application Serial No. 251,099, filed May 8, 1972 [correspondingly

the DP-PS (German patent application P 23 23 191.6)]

can be vinyl laalide or

a vinyl halide comonomer mixture in a single-stage or two-stage bulk reaction in the presence of about 0.05 to about 20% of a Polyolefinkautschuks having a molecular weight in the range of from about 50 thousand to 1 million or higher to form a Polyvinylhalogenidproduktes polymerized v / earth, both free , that is, contains dispersed as well as grafted polyolefin and has very good impact resistance and other desirable properties such as reduced melt viscosity. It has now been found that polymers with particularly good impact strengths are on the order of about 1.38 to 2.76 kpm / 2.54 cm (10-20 ft-lbs / in.) Or

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more can be obtained if, in the corresponding process, the amount of polyolefin fed in is above about 3.5% by weight, preferably above about 5.3% by weight, based on the vinyl halide concentration. It has been found, however, that the use of such high concentrations of polyolefins, particularly polyolefins with molecular weights above 150,000, gives difficulty in mixing the reaction mass and results in a product having a relatively low proportion of a finely divided particle and a substantial number of relatively massive lumps or agglomerates . In the above-mentioned polymerization, as soon as the stirred reaction mixture is heated to initiate the polymerization, the polymerization mass changes from an essentially clear solution or dispersion of the polyolefin in vinyl halide or vinyl halide comonomer mixture to a milky, opaque emulsion. After about 1 hour the reaction mass becomes a paste and after about 1.5 hours of reaction time, which corresponds to a conversion of about 25 to 30% vinyl halide to polymer, the reaction isotherm shows a rapid increase with a simultaneous thickening of the paste, ie it develops "thick paste state" in the reaction mass. After about 40 to 5% conversion of the vinyl halide monomer to the polymer, the thick paste becomes mainly a fine, non-viscous powder. If high concentrations of polyolefin are added to the reaction mass to produce the above-mentioned polymer having excellent impact resistance, the thick paste state of the reaction mixture becomes so viscous, that is, it has a consistency substantially similar to that of unbaked dough, that stirring or a movement of the mixture hardly shows a mixing effect in the polymerization mass. In other words, the reaction mass consists of several large, dough-like agglomerates or, in extreme cases, a single, dough-like lump that adheres or moves around or rotates around the agitator or stirrer. If the reaction is different from the previously

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written thick paste state is continued until completion, the product contains a relatively small proportion of uniformly shaped, finely divided particles, compared to the proportion of such powdery material that is obtained when the polyolefin in low concentrations, ie in amounts of 5.3 % By weight or less or in particular from 3 »5% by weight or less, based on the vinyl halide used, is added. The product also contains one or more massive, irregularly shaped agglomerates, the agglomerate or agglomerates in extreme cases containing a major part or a predominant part of the polymer product. The particulate product of the above-mentioned process normally has hard, molten surfaces and generally the large particles contained therein must be comminuted, for example by milling or an equivalent pulverization process, so that they are suitable for normal polymer processing steps. The latter methods generally involve handling the polymer in a fluid, molten state. Accordingly, polymers containing the aforementioned large particles or massive agglomerates require large, costly energy inputs to pulverize the particles. Alternatively, the direct melting or fusion of the massive agglomerates and a large proportion of relatively large particles requires the products contained in general, a prolonged heating of the product can be adversely affected whereby the polymer color and / or the polymer may decompose. The large product particles and agglomerates obtained when using the above-mentioned relatively high amounts of polyolefin in the above-mentioned process are generally less homogeneous than small product particles because of the high local concentrations of monomer, polyolefin and reaction initiator large particles will accumulate and particularly within the massive agglomerates if there is no effective mixing within these large particles during their formation in the

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thick paste state takes place. Furthermore, the bad Heat transfer within the relatively massive mass of these particles increases the homogeneity of the polymer within the particles adversely affected.

In the process described above, there is generally stirring or movement of the polymerization mass required, but, as stated above and as can be seen from Example 2 below, such a movement or such stirring does not avoid the formation of product agglomerates, and undesirably form in the product large proportions of large particles if the large concentrations of polyolefins described above during the polymerization be used. An increase in the stirring or moving speed in the reaction would not be a suitable method for eliminating the above-mentioned disadvantages of the above Process, since in the thick paste state of the polymerization, in which the undesired agglomerates and large particles are formed, the dough-like reaction mass is on the rotating or moving stirrer or the corresponding agitator would accumulate and rotate with it. An increase in the stirring speed would hence no increase in internal mixing in the agglomerated reaction mass, and at extremely high stirring speeds the stirrer or the stirrer motor could be damaged.

According to the invention, the disadvantages of the known method are eliminated. The invention relates to a method for the preparation of a vinyl halide polymer in which in the bulk a vinyl halide monomer in the liquid phase is either alone or together up to about 50% by weight of another ethylenically unsaturated monomer which can be polymerized with it is, in the presence at the beginning of more than about 1.8 wt.%, Based to the vinyl halide monomer, a polyolefin, or

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polymerized a mixture of polyolefins having a weight average molecular weight of at least about 50,000. The improvement according to the invention consists in that _f removed from the polymerization mass during their thick paste state, a sufficient amount of vinyl halide in the polymerization mass or from the polymerization mass, relative to the effective concentration of polyolefin to above about 3.5 wt. # On the in mass vinyl halide remaining after removal of the vinyl halide, whereby the polymerization mass agglomerates are broken and a more finely divided, fine-shaped product with high impact resistance is obtained.

In general, the method according to the invention enables relatively high effective concentrations of polyolefin in the above-mentioned vinyl halide polymerization process the DT-OS 23 23191 or US-Note. No. 674 202. A finely divided polymer product with a relatively high concentration on grafted polyolefin, ζ. Β. over 6,096, usually over 8%, based on the weight of the product, and thus improved impact resistance, e.g., about 1.38 to 2.76 kpm / 2.54 cm (10-20 ft.- lbs./in.), as determined by the Notched Izod Impact Test (ASTM D-256) can be obtained. Removal of vinyl halide monomer according to the present invention gives a more finely divided product than if this removal were not carried out. That is, the proportion of particles smaller size, i.e. particles with a cross-sectional width less than about 1.2 mm, in the product increases significantly, typically to about 200% or more, and the maximum product particle size is reduced significantly, typically by 2O times or more what from a comparison of the results of Examples 1 and 2 below. For the production of a homogeneously powdered, for the known polymer processing suitable polymers is much less

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mechanical work is required for the comminution of the polymer products according to the invention than they are for comparable, agglomerated Polymers, which are produced by known methods, is required. Alternatively, it was found that, . if the polymers according to the invention are to be processed without a previous reduction step, those according to the invention finely divided polymers generally require less heating to melt than their counterparts Products of the above-mentioned process, the massive agglomerates and much larger proportions of large particles contain. When melting, the polymer products according to the invention are exposed to extreme temperatures for shorter times, and in doing so, the adverse effects such temperatures have on polymer stability and color can, eliminated. Since the products according to the invention have a Have a much larger proportion of particles of smaller size and the massive product agglomerates that occur in the known Processes obtained do not include when an effective polyolefin concentration is above about 3.5% or particularly above About 5.3% is used, the particulate product according to the invention also has a more homogeneous constitution than the product of the known process.

It was surprising to find that removal of the vinyl halide monomer according to the invention was effective the breaking up of the reaction mixture agglomerates is, as is generally the case in the known processes in which a vinyl halide bulk polymerization occurs, it is indicated that the removal is undesirable, or it is indicated that a Adding vinyl halide to the polymerization mass breaks up the agglomerates. In US-PS 2,230,240, in which the bulk polymerization a vinyl compound, e.g. vinyl halide, and a maleic anhydride comonomer is described, it is required that the reaction is carried out at a sufficient reaction pressure so that the escape of the vinyl

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monomers is prevented, since such removal by blowing off causes the polymerization mass to bubble up, as a result of which the homogeneity of the product is impaired. In U.S. Patent No. 2,961,432, in which the bulk polymerization of a vinyl compound such as vinyl halide, in the presence of one of its polymers is described, is further provided (see FIG., Column 3, lines 15 to 21), that it is particularly preferred that the vinyl monomer to be added in vapor form to the stirred or agitated polymerization mass, so that agglomeration of the reaction mixture is avoided. This teaching is in contrast to the improvement level of the present invention.

Except for the above-mentioned improvements according to the invention, the reactants and the reaction conditions, e.g., the reaction temperature and pressure, are im essentially the same as that in the aforementioned US patent application Serial No. 674 202 or in Dt-OS 23 23191 described polymerization process.

The vinyl halide used in the present process is preferably a vinyl chloride, although other vinyl halides such as vinyl fluoride and vinyl bromide can also be used.

In carrying out the process of the invention , the vinyl halide monomer can be removed from the thick paste state of the agitated polymerization reaction mass in any suitable manner. For example , the liquid monomer can be removed from the bulk reaction mass, for example by passage through a pressure filter. The filtrate is then distilled out of the reaction vessel, wherein the initiator and unreacted polyolefin-containing distillation residue is Siert recycli- in the reaction vessel. Since the polymerization is generally at least

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is carried out under autogenous superatmospheric pressure. especially when vinyl chloride is the vinyl halide reactant is used, the removal of the vinyl halide is preferably achieved by the reaction equipment in venting a pressure zone, e.g., the atmosphere, where the pressure is substantially below the reaction pressure lies. Removal by blowing off is particularly preferred, since this ensures rapid removal of the heat from the reaction mass. Removal of the vinyl halide monomer begins during the above-described thick paste state of the conversion, the duration of the conversion to a Polymer from about 25 to about 45 weight percent, more typically about 30 to about 40% by weight, vinyl halide, based on the added vinyl halide. The beginning of the thick paste state is generally due to a rapid increase. accompanied by the V / arm formed during the implementation, i.e. by a rapid increase in the reaction isotherms caused by a sharp increase in the reaction pressure can be seen. The vinyl halide removal according to the invention is preferably started about 5 minutes to about 15 minutes after the start of the thick paste state in the polymerization. Blowing off vinyl halide from the reaction mass according to the preferred removal of the vinyl halide can be continuous or alternatively and preferably carried out intermittently, i.e. periodically, and regularly, with the reaction mass increasing can restore, d. H. after each release of vinyl halide it can be the same temperature and the same Assume the pressure in the reaction chamber before each release or release of monomers have prevailed. The polymerization vessel is preferably adjustable in a suitable manner Valve equipped to facilitate blow-off.

The amount of vinyl halide monomer that is removed in the present invention during the thick paste state of the polymerization reaction to avoid product agglomerates is

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generally a small proportion of the vinyl halide used in the polymerization, ie less than about 50% by weight , based on the vinyl halide introduced. In order to retain all of the advantages of the above-described polymerization process of U.S. Patent Application Serial No. 674,202, it is preferred to add no more than about 40 wt. 56, typically no more than about 30 wt. 96, of the vinyl halide fed in the polymerization removed the inventive method. While certain improvements in the production of finely divided polymer products of small maximum particle size can be achieved by removing only a very small amount, e.g., 2-3 wt.% Vinyl halide, during the thick paste state of the polymerization, it is preferred in the practice of the present invention to remove at least about 5% by weight of the vinyl halide fed. Preferably, the percentage of vinyl halide removed varies from about 8 to 15 to about 25 to 35 percent, and more preferably is from about 15 to 35 percent based on the vinyl halide introduced.

The rate of removal of the vinyl halide by blow-off or by a removal process can be within one can be varied over a wide range. It is preferably about 0.1 to about 1.5%, preferably about 0.15 to 1.2% / min, based on based on the weight of the vinyl halide introduced. Particularly good results are generally obtained when the vinyl halide is removed from the polymerization mass at a rate ranging from about 0.3 to about 0.8 to up to about 1.0 or even up to about 1.2 wt% / min.

The proportion of vinyl halide and polyolefin which are used at the beginning of the polymerization can vary over a wide range but should be sufficient that a distance after the vinyl halide in the thick paste state

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effective polyolefin concentration of about 3.5 to about 20 wt.%, Preferably of at least about 5-3 and in particular about 5.5 to about 10 wt present invention remains, ie based on the amount of vinyl halide that is fed minus the amount of vinyl halide that is removed in the thick paste state of the polymerization, is present. A particularly good result is generally obtained when the initial supply of polyolefin and vinyl halide and removed during the thick paste state of the reaction amount of vinyl halide sufficient to provide an effective polyolefin concentration of about 6 to about 8, or even up to about 9 wt.% To give . Typically, the initial polyolefin and vinyl halide concentrations in the polymerization will be chosen to provide a reaction mixture which prior to blown or otherwise vinyl halide removal is above about 1.8 and preferably at least about 3 percent, typically about 3.596 or more, based on polyolefin based on the weight of the supplied vinyl halide.

Although the exact chemical nature of the polymer formed in the process of the present invention is not known, it is believed that a graft copolymer is formed in which the vinyl halide polymer forms on the polyolefin polymer. In order to obtain a maximum reduction in melt viscosity, which is taken as the standard measure of processability, the polymer used as the parent polymer in the graft polymerization should be incompatible with the vinyl halide polymer formed. During processing of the vinyl halide polymer, such as deformation, the physical properties of the polymer change during processing as a result of the polymer being held at high temperatures for long periods of time and the heat accumulated inside as a result of shear forces which

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If

are generated by the processing devices. The physical Properties of a graft polymer with a parent polymer compatible with the vinyl halide polymer can change during processing as a result of the solubilization of the parent polymer into the polyvinyl halide. In such a case, the impact resistance decreases during processing. The compositions according to the invention or Masses refer to graft copolymers with a polyolefin backbone polymer, which is incompatible with the vinyl halide polymer formed thereon. With such an incompatible polymer backbone, the physical properties of the graft copolymer do not change during the Processing as the incompatibility prevents solubilization of the parent polymer in the polyvinyl halide. the Melt viscosity is reduced by the choice of graft copolymer and is determined by the normal processing conditions that follow unaffected.

The melt viscosity of the graft copolymer formed also depends on the molecular weight of the parent polymer as well as the vinyl halide polymer formed thereon. Maximum reduction in melt viscosity can be expected in a graft copolymer where the parent polymer is selected to have a low molecular weight, e.g., a weight average molecular weight of 50,000 to 150,000, and the vinyl halide monomer is polymerized so that it has an acceptable molecular weight, with such low molecular weight olefin polymers being preferred as they are particularly easy to process in the molten state. For the production of polymer products with good impact resistance, ie with a high graft polyolefin content or a high graft yield, the weight average molecular weight of the polyolefin is preferably in the range from about 150,000 to about 1,000,000 or higher and in particular from about 150,000 to about 400,000 .

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Although vinyl chloride in the present invention When the preferred vinyl halide reactant is other suitable vinyl halide monomers are useful in the present invention Invention can be used, the oc-halogen substituted, Ethylenically unsaturated compounds that are similar to vinyl chloride in an addition polymerization reaction can participate, such as vinyl fluoride, vinyl bromide, vinyl iodide, Vinylidene fluoride, vinylidene chloride, vinylidene bromide, vinylidene iodide, and others. The polymers of the present invention can from the same or different oc-halogen-substituted, Ethylenically unsaturated materials, and the invention thus includes homopolymers, copolymers, terpolymers and interpolymers formed by addition polymerization. An example of such copolymers is a copolymer of vinyl chloride and vinylidene chloride.

Although it is preferred that the monomer composition consisting entirely of vinyl halide monomers, e.g., vinyl chloride alone, are supported by the present invention also includes copolymers obtained by free radical addition polymerization of a monomer mass having a predominant amount, e.g. at least 50% by weight, vinyl halide and a minor amount, e.g., less than 50% by weight, of another Ethylenically unsaturated monomer composition which is copolymerizable therewith contains. The other is preferred Ethylenically unsaturated monomers in amounts of 20% by weight or less and most preferably in amounts of 10% by weight or less based on the total monomer used to make the polymer is used. Suitable ethylenically unsaturated Compounds used to form copolymers, terpolymers, tetrapolymers, interpolates, and others are, for example, the following monoolefinic hydrocarbons, i.e. monomers containing only carbon and hydrogen contain including such materials as ethylene, propylene, 3-methylbutene-1, 4-methylpentene-1, pentene-1, 3,3-di-

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methylbutene-1, 4,4-dimethylbutene-1, octene-1, decene-1, styrene and its derivatives which are α-alkyl or aryl substituted on the nucleus, e.g. o-, m- or p-methyl-, -ethyl- , -Propyl- or -butylstyrene, α-methyl-, -ethyl-, -propyl- or -butylstyrene; Phenylstyrene and halogenated styrenes such as cc-chlorostyrene; monoolefinically unsaturated esters including vinyl esters, for example vinyl acetate, vinyl propionate, vinyl butyrate, vinyl stearate, vinyl benzoate, vinyl p-chlorobenzoates, alkyl methacrylates, for example methyl, ethyl, propyl and buty methacrylates; Octyl methacrylate, alkyl crotonates, for example octyl; Alkyl acrylates, for example methyl, ethyl, propyl, butyl, 2-ethylhexyl, stearyl, hydroxyether and tert-butylamino acrylates, isopropenyl esters, for example isopropenyl acetate, isopropenyl propionate, isopropenyl butyrate and isopropenyl isobutyrate; Isopropenyl halides, for example isopropenyl chloride; Vinyl esters of halogenated acids, for example vinyl-α-chloroacetate, vinyl-α-chloropropionate and vinyl-α-bromopropionate; Allyl and methallyl esters, for example allyl chloride, allyl cyanide; Allyl chlorocarbonate, allyl nitrate, allyl formate and allyl acetate and the corresponding methallyl compounds; Esters of alkenyl alcohols, for example ß-ethylallyl alcohol and ß-propylallyl alcohol; Halo-alkyl acrylates, for example methyl-a-chloroacrylate and ethyl-a-chloroacrylate, methyl-a-bromoacrylate, ethyl-a-bromoacrylate, methyl-a-fluoracrylate, ethyl-a-fluoroacrylate, methyl-α- iodoacrylate and ethyl-α-iodoacrylate; Alkyl-a-cyanoacrylates, for example methyl-a-cyanoacrylate and ethyl-a-cyanoacrylate, and alkyl-a-cyanoacrylates, for example methyl-a-cyanoacrylate and ethyl-a-cyanoacrylate; Maleates, for example monomethyl maleate, monoethyl maleate, dimethyl maleate, diethyl maleate; and fumarates, for example monomethyl fumarate, monoethyl fumarate, dimethyl fumarate, diethyl fumarate; and diethyl glutaconate; monoolefinically unsaturated organic nitriles including, for example, fumaronitrile, acrylo nitrile , methacrylonitrile, ethacrylonitrile, 1,1-dicyanopropene-1, 3-octenenitrile , crotonitrile and oleonitrile; monoolefinically unsaturated carboxylic acids including e.g. acrylic acid, meth acrylic acid, crotonic acid, 3-butenic acid, cinnamic acid, maleic acid,

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Fumaric acid and itaconic acid, maleic anhydride and others amides these acids, such as acrylamide, are also suitable. Vinyl alkyl ethers and vinyl ethers, e.g. B. vinyl methyl ether, vinyl ethyl ether, Vinyl propyl ether, vinyl n-butyl ether, vinyl isobutyl ether, Vinyl 2-ethylhexyl ether, vinyl 2-chloroä "chyl ether, vinyl propyl ether, Vinyl n-butyl ether, vinyl isobutyl ether, vinyl 2-ethylhexyl ether, Vinyl 2-chloroethyl ether, vinyl cetyl ether u. Ä., And vinyl sulfides, e.g. vinyl-ß-chloroethyl sulfide, vinyl-ßäthoxyäthylsulfid and others, can also be used. Diolefinically unsaturated hydrocarbons, the two olefinic Contain groups in conjugate relationship, and their halogen derivatives, e.g. butadiene-1,3 »2-methyl-butadiene-1,3» 2,3-dimethylbutadiene-1,3, 2-methylbutadiene-1,3, 2,3-dimethylbutadiene-1,3, 2-chlorobutadiene-1,3, 2,3-dichlorobutadiene-1,3, and 2-bromobutadiene-1,3, among others, can also be used.

Specific monomer compositions for the production of copolymers are, for example, vinyl chloride and / or vinylidene chloride and vinyl acetate, vinyl chloride and / or vinylidene chloride and maleic or fumaric acid esters, vinyl chloride and / or Vinylidene chloride and acrylate or methacrylate esters, vinyl chloride and / or vinylidene chloride and vinyl alkyl ethers. These are given as examples of the numerous combinations of monomers used to form the copolymers can, listed. All such combinations or mixtures are included in the present invention.

The bulk free radical polymerization of the monomer mass or composition is in the presence of a Olefin homopolymers, copolymers, terpolymers or tetrapolymers and their halogenated derivatives. The olefin polymers can also use a diene as a monomer unit contain.

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Suitable monomers are propene, butene-1, isobutene, pentene, hexene, heptane, octene, 2-methylpropene-1, 3-methylbutene-1, 4-methylpentene-1, 4-methylhexene-1, 5-methylhexene-1.

Suitable comonomers are those used for production of homopolymers, as indicated above, are used such as propene or butene-1 with ethylene or isobutylene with isoprene, Ethylene with vinyl acetate, ethylene with ethyl acrylate, etc. Suitable termonomers are those used for the production of Horopolymers and copolymers as described above, such as propene, ethylene, etc., which are up to 15% by weight, are preferred up to about 6% by weight, of a diene such as dicyclopentadiene, butadiene, cyclooctadiene and other non-conjugated Serve with linear or cyclic chains.

The polyolefins used are characterized by the fact that they can be used at normal room temperature and normal pressure Vinyl chloride monomers are soluble, partially soluble or dispersible, and when they are a homopolymer, monomer units of 2 to 8 carbon atoms, when they are copolymers, have mono-atomic units of 2 to 8 carbon atoms and when they are a halogenated polymer, have monomer units of 2 to 8 carbon atoms. Suitable Halogenated polyolefins are the chlorinated, brominated or fluorinated polyolefins. The weight average Molecular weight of olefin polymers, copolymers, terpolymers and tetrapolymers can vary from about 50,000 to about 1,000,000 and higher as described above.

The bulk polymerization by free radicals may in the present process at temperatures between about 25 and about 90 ° C, preferably about 40 to about 80 ° C and most preferably about 50 to about 75 ⁰ C, to proceed. The polymerization reaction is carried out in the presence of a small, initiating amount of a free radical initiator for

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implementation carried out. Suitable initiators for free radicals are organic or inorganic peroxides, persulfates, oxonides, hydroperoxides, peracids and percarbonates, diazonium salts, diazotates, peroxysulfonates, trialkylborane oxygen systems, amine oxides and azo compounds such as 2,2'-azobis-isobutyronitrile and 2.2 ^l -Azo-bis-2,4-dimethylvaleronitrile. An azo compound or an organic peroxy compound, in particular an organic peroxide, is preferably used as the initiator. The initiator is used in a concentration in the range from about 0.01 to about 1.0 percent, and preferably from about 0.05 to about 0.5/0, based on the total weight of all monomers in the reaction mixture. Organic initiators which have particularly good solubility in the bulk polymerization composition are described in the aforementioned DT-OS 23 23191.6, and such are particularly useful in the practice of the present invention. They include, for example, the following compounds: lauroyl peroxide, benzoyl peroxide, diacetyl peroxide, azo-bis-isobutyronitrile, diisopropyl peroxydicarbonate, azo-bis-isobutyramidine hydrochloride, tert-butyl peroxypivalate, 2,4-dichloro-benzoyl peroxide and 2,2'-azobis- ( 2,4-dimethylvaleronitrile). These and other suitable initiators are described in more detail by J. Brandrup and EH Immergut, Editors “Polymer Handbook”, Interscience Publishers, 1966, Chapter II entitled “Decomposition of Organic Free Radical Initiators”. The initiator is preferably selected from a group of initiators which are known as "hot catalysts" or as those which have a high degree of free radical initiator activity. Initiators with a lower degree of activity are less suitable because they require longer polymerization times. A long polymerization time can furthermore cause the product to decompose prematurely, which can be recognized by discoloration, for example a pink discoloration.

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The process according to the invention is preferably carried out as a single-stage mass polymerization process. If appropriate or if desired, the reaction can be carried out as a two-stage reaction, with the first Stage high speed is used and high shear agitation is used and with the second stage is stirred at low speed and low shear. Two-stage bulk polymerization process for Vinyl halide and vinyl halide comonomer mixtures which can be used in the present invention can be used in the aforementioned DT-OS 23 23191.6 as well as in British Patent 1,047,489 and U.S. Patent 3,522,227.

In the following, abbreviated description of a typical, two-stage reaction procedure for the implementation of the process according to the invention, for the sake of simplicity, the initial stage of the polymerization or copolymerization is used referred to as the first stage response. The reaction vessel in which this initial polymerization stage is carried out is referred to as a "prepolymerizer". the final or final stage of the polymerization is simply a reaction the second stage, and the reaction vessel in which this is carried out is called the "polymerizer" designated.

In the reactor of the first stage, the devices for moving or stirring the monomer or the Monomers used are chosen so that they give shear agitation. Such a facility is generally used referred to as "a radical turbine type agitator". In the prepolymerizer is at the beginning of the first Step filled with a monomer composition, to which an initiator is added. Any polymerization that is common is used in bulk polymerization processes, i.e. one of the types described above, as far as it is used for

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Bulk polymerization process is suitable, can be used. After the vinyl chloride monomer is added to the first stage reactor, the process of removing air from the first stage reactor vessel ventilates a minor amount of the monomer. In the first stage reactor, the turbine-type stirrer speed is generally between about 500 and 2000 rpm or a tip speed of about 2 to 7 m / sec is used. A tip speed of at least about 0.1, and preferably about 0.5 to about 2 meters / sec is used with the second stage reactor. These values should not be viewed as limit values. Once a conversion of at least about 3 to about 20% of the monomer mass is obtained in the first stage reactor, the contents of the reactor are placed in a second stage polymerizer equipped to allow agitation at lower levels Speed and low shear force is achieved so that appropriate temperature control is achieved in the reaction medium. Preferably the conversion in the first stage reactor is from about 3 to about 15 percent, and more preferably from about 7 to about 15 percent. The reaction temperature in the reactors of the first and second stages is generally in the range of about 25 to about 90 ⁰ C, preferably about 40 to about 80 ⁰ C. The reaction pressure in the reactor of the first stage is at least autogenous superatmospheric pressure and is located in the generally in the range of about 5.62 to about 14.1 kg / cm (80-210 psi), and preferably about 6.33 to about 13.4 kg / cm ² (90-190 psi).

Since the minimum conversion (e.g. about 25 to 30%) of vinyl halide that occurs at the start of the thick paste state of the Polymerization corresponds, unchanged in the second reaction stage of the two-stage reaction process described above takes place, the vinyl halide monomer in the present invention is always from the second stage of the two-

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step reaction process removed. The temperature, pressure and agitation conditions of the second stage are essentially similar and thus typical of those used when the improved polymerization process of the present invention is shown in FIG a single reaction stage is carried out.

The improved polymerization product of the present invention is derived from the polymerization reaction vessel itself known method, e.g. by removing the unreacted monomers by blowing off. The finely divided according to the invention Products can easily be ground or otherwise crushed to a homogeneous powder, which with known, inert additives such as fillers, dyes and pigments can be mixed. The polymerization products can continue using plasticizers, lubricants, thermal stabilizers, and ultraviolet and light stabilizers each mixed as needed. If appropriate, the products according to the invention can be used directly for mixing with those described above Additives are melted, and then melt processing such as molding and extrusion can be performed take place. The melting or amalgamation of the polymers of the invention, which are mainly finely divided particles contained, takes place so quickly that any strong decomposition or discoloration, caused by the action higher temperature while melting or fusing is avoided.

The exact mechanism by which the reaction mixture agglomerates are comminuted in the process of the invention or are broken up is not fully known. Although the present invention is not believed to be limited to any Theory should be limited that the inventive removal of the vinyl halide the ratio of solid phase, i.e. from polymer to liquid phase, i.e. vinyl halide monomer,

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contains the dissolved or dispersed polyolefin in which Reaction mass increases and that thereby the reaction mass very quickly from the thick paste state into a fluid, powdery State, as described above, passes.

The following examples illustrate the invention. Unless otherwise stated, the parts, percentages and ratios by weight and temperatures are given in ⁰ C in the description and in the claims.

example 1

In a 2 l cylindrical glass reactor, which is equipped with a stirrer with an insertion rod, which is operated at about 200 rpm and a tip speed of about 0.1 m / sec, a pressure sensor and a blow-off valve, and which is surrounded by a jacket , which contains an aqueous heating bath at constant temperature, are given 45.0 g of a polyolefin mixture _{with a weight average molecular weight of 330,000, which is a 3: 4 mixture of 19 f} 3 g Epsyn 7006 (an ethylene-propylene copolymer with a weight average molecular weight of 225,000, manufactured by Copolymer Corp.) and 25 »7 g of SK43A (an ethylene-propylene copolymer having a weight average molecular weight of 420,000, manufactured by Copolymer Corp.), and 0.7 g of lauroyl peroxide initiator. The test of whether the reactor is leakproof is carried out by pressurizing the reactor with nitrogen. It is then evacuated to a sub-atmospheric pressure of about 5 mm. 745 g of vinyl chloride are poured in. After sealing the reactor, approximately 80 grams of vinyl chloride is vented from the reactor to remove trapped air. This corresponds to a net charge of about 665 grams of vinyl chloride and an initial polyolefin concentration of about 6.77 percent based on the weight of the vinyl chloride. The reaction mass is stirred to a temperature of about

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Heated 70 to 72 ° under autogenous pressure of about 12.0 to 13.3 atmospheres (170-175 psig) to initiate polymerization. The polymerization mass changes from an essentially clear solution or dispersion to a cloudy slurry. After about 1.5 hours there is a strong increase in the reaction exotherms, ie in the heat given off by the reaction mass, which can be recognized by an increase in the reaction pressure. At about the same time, the consistency of the reaction mixture becomes similar to that of a dough, indicating that the thick paste state of polymerization is beginning. After about 5 minutes from the exothermic rise, the reactor blow-off valve is opened periodically but regularly over the course of 30 minutes to blow off about 8% of the vinyl chloride (based on the net filled vinyl chloride) into an exhaust at atmospheric pressure at an average rate of about 0.267 o / min, so that the effective concentration of polyolefin is about 7.3756 (based on the net filled vinyl chloride minus blown vinyl chloride). After the blowing off or letting out is complete, the polymerization continues rapidly to the powdery polymerization state, ie the polymerization mass changes from a very viscous, dough-like paste to an essentially fine, non-viscous powder. The reaction can proceed under the temperature, pressure and stirring conditions described above until no more liquid monomer is found in the reactor and the pressure therein begins to fall, v / as indicates the end of the polymerization. The duration of the polymerization from the start of initiation is about 2.9 hours.

The reactor is vented to the atmosphere to remove residual vinyl chloride. The particulate Polymer in the reactor (313 g) together with the scraped-off residues from the reactor bottom and walls and the stirring device, i.e. the bottom cake, the wall deposits and the stirrer deposits (61 g, about 16.3% of the total product),

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result in a product yield of 374 g, of which about 12.3% Polyolefin in both grafted and three dispersible forms, so that the amount of polymer that can be removed from the Vinyl chloride obtained is 329 g, which corresponds to a conversion of about 50% based on the net filled vinyl chloride the implementation.

The particulate part of the product is then through Sieve a sieve with 1.2 mm (16 mesh U.S. Standard sieve size) openings. The amount of particulate! Polymer fines or particulate !, powdery]! Polymer, i.e. particles with an average cross-sectional width of about 1.2 mm or less that passes through the sieve is 108 grams (about 29% based on total poly product). The amount of particulate polymer remaining on the screen, i.e. polymer particles with an average cross-sectional width over about 1.2 mm, is 205 g (55? o) of which about 114 g of substantially uniform, granular polymer particles having an average cross-sectional width of about 1.2 to about 10 mm, about 49 grams are spherical polymer particles with an average cross-sectional width of about 10 to about 25 mm and about 42 g in the form of three irregular Agglomerates or clumps are present with an average cross-sectional width (determined by their widest Dimension) of about 30 mm.

The impact strength according to the Notched Izod Impact Test according to ASTM-D256 method of the particulate fraction of the product described above is determined. Samples for use in this experiment are prepared by adding 100 parts of polymer, 5 parts of Acryloid K12O-ND (an acrylic polymer processing aid manufactured by Rohm & Haas Co.), and 2 parts of Thermolite 32 [di-n-butyltin-S, S ¹ bis (isooctyl mercapto acetate) thermal stabilizer manufactured by M and T Chemicals Inc.]. The mixture

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is on a two-roll Farrell mill for 5 minutes at about .188 ° ground and formed into a sheet or plate with a thickness of 0.32 mm (1/8 in.) on a Carver press. The foil or plate is in uniform 1.27 cm χ 6.35 cm (0.5x2.5 in.) Test pieces cut.

The Izodr ^ impact strength (notch) is excellent and ranges from about 1.38 to 2.52 kpm / 2.54 cm (10-18 ft.-lbs.per in.).

The percentage of graft in the polymer product is determined by extracting the free, ungrafted polyolefin and vinyl chloride homopolymers and isolating the vinyl chloride-polyolefin graft polymer from the polymer product using a procedure similar to that described in Example 3 of US Pat US patent application 674 202 or DT-OS 23 23191 is described. According to a known analytical method, the percentage of chlorine in the vinyl chloride-polyolefin graft polymer is analyzed. To determine the percentage of vinyl chloride in the graft copolymer, the obtained percentage of chlorine is divided by 56.890, the percentage of chlorine in a known vinyl chloride homopolymer. The latter percentage, after subtracting 100, gives the percentage of grafted polyolefin in the graft polymer. From the latter percentage and the percentage of free grafted polyolefin in the product, the percentage of grafting in the total polymer product can be calculated. The polymer product according to the invention has a percentage of grafting of 8h% (corresponding to a vinyl halide-polyolefin graft polymer content in the product of about 10.3%).

809822/0497

Examples 2 to 6

In Examples 3 to 5, the procedure of Example 1 is essentially repeated, with net amounts being Vinyl chloride from about 660 to 670 g vinyl chloride can be used and with various process parameters, as in shown in the table below. The table shows the results of these tests in comparison with those of Example 1 summarized. Examples 2 and 6, the results of which are also summarized in the table, are Comparative Examples which are run using essentially the same process conditions as the Examples 1 and 3 through 5 are used with the exception that no vinyl chloride is used during the paste state of polymerization Will get removed.

From a comparison of the results of Examples 1 and 3 to 5 with those of Comparative Example 2 it is evident that the inventive removal of vinyl chloride monomer during the thick paste state is a vinyl chloride-polyolefin polymer with high impact strength and improved small particle size, i.e. a larger proportion of the product is a particulate polymer with an average cross-sectional width of less than about 1.2 mm, whereas the average cross-sectional width of the largest particles from about 700 mm (Comparative Example 2) to about 30 mm (as in Example 1) was reduced.

A comparison of the results of Comparative Example 6 with those of Examples 1 to 5 further shows that very good impact strength, as determined by the very sensitive Notched Izod Impact Strength Test, is obtained when the percentage of grafted polyolefin contained in the polymer product is over about 6% .

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'ft-

Comparative Example 6 shows that an initial concentration of 5.3% polyolefin in the polymerization reaction mass a polymer product having the desired small particle size but that small Concentration of polyolefin in the reaction mixture, if it remains as the effective polyolefin reaction concentration and if the inventive monomer removal step is not carried out, a low graft polyolefin poly product, i.e. 6% or less. The product is therefore unsatisfactory because it is inferior Impact resistance possesses as the products of the respective examples 3 to 5. In the latter examples, the Polymerization compositions have an initial polyolefin concentration of about 5.3%, as in Example 6, but by that of the invention Monomer removal in these examples will reduce the effective polyolefin reaction concentration to about 6.9 to about 7.6% increased, resulting in products with improved impact resistance results.

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Ex. Net trains - during d. led thick pa vinyl chlo- stenzustands rid (g) blown vinyl chloride

Tabel

% added Effective lower % polyols-polyolefin concentration

Blow-off time d.

rate
( ^c / o / min)

Beginning
d. blowing off after
Start d.
thicker.
State of the past (min)

Duration d. % Conversion

Abla-

sens

(min)

v. vinyl chloride (duration of reaction)

1

2 (comparison)

3

4th

5

6 (cf.)

no 6.77 30th 5.3 24 5.27 27 5.23 none 5.3

7.37

6.77 7.57 6.92 7.15 5.3

0.267

10
20th

30 60 (2.9 h)

0 58 (4.3 h)

25 41 (2.3 h)

30 47 (2.6 h)

30 44 (2.3 h)

0 71 (3.5 h)

CD CO CD

Table (continued)

Example % total
polyolefin
In the product 12.3 % Grafting
(°, 3 grafted
Polyolefin im
Product) Particulate product
% Total product % total product
£ about 1.2 mm duct> about
Cross-sectional 1.2mm cross
wide cutting width 55 Biggest part
size in
d. particulate
Product (mm) % non-part-
small-shaped
product 1 ■) 1O, 4 84 (10.3) 29 82 80 16 2 (cf. 11.5 83 (8.7) 11 48 700 7th 3 10.0 - 36 27 ■ - 14th 4th 10.5 85 (8.5) 57 30th 5 16 VJl .) 7.0 79 (8.8) 54 22nd 16 16 6 (cf. 86 (6.0) 60 15th 16

Comment:

The particulate products of Examples 1 to 3 and 5 have excellent ' Notched impact strengths in the range of about 1.38 to 2.54 kpn / 2.54 cn (10-18 ft.lbs / in). The particulate product of Example 4 has very good ultimate impact strength of 2.68 kpm / 2.54 cm (19 ft.lbs / in.), whereas the impact strength of the particulate Product of comparative example 6 is very poor and only about 0.27 kpn / Is 2.54 cm (2 ft.lbs./in.).

Example]. 7th

The procedure of Example 1 is essentially as described therein, with the exception that the net feed of vinyl chloride is 670 g; and that 42.5 g of a mixture (weight average weight average Molecular weight 390,000) from 10 g Epsyn 7006 and 32.5 g SK 43A as polyolefin, corresponding to an initial polyolefin concentration of 6.34%, based on the net filled Vinyl chloride, used v / ground. The vinyl chloride removal is started 10 min after the increase in the reaction exotherms, which indicates the beginning of the thick paste state of the polymerization. The vinyl chloride is blown off for 15 minutes to remove of about 10% of the filled vinyl chloride (which is a effective polyolefin concentration of about 7.05%) at an average rate of about 0.33% / min. The reaction time is about 2.8 hours. The particulate Polymer in the reaction vessel (321 g) along with the cake from the bottom of the reactor (41 g), the deposit on the reactor wall (16 g) and the deposits on the stirrer (50 g) give a product yield of 371 g. There is approximately 11.5% polyolefin in grafted and freely dispersed form so that the conversion of vinyl chloride to polymer is 328 g (52%). When sieving the particulate portion (321 g, 71% of the total product) 98 g (26%) with an average Particle width below about 1.2 mm, 166 g (45%) with an average particle width above about about 1.2 mm obtained. Of this, 89 g is a substantially uniformly shaped, granular polymer with an average Section width from about 1.2 to about 5 now and 77 g are spherical agglomerates with an average Cross-sectional width over about 5 mm. The maximum cross-sectional width of these agglomerates is about 15 mm. Particle with a width of less than about 1.2 mm and those with a width between about 1.2 and about 5 mm have one Total content of 10% polyolefin, where the percentage

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of grafting is about 90% (equivalent to about 9% grafted polyolefin in the product) and a Notched Izod Impact Strength of about 2.2 kpm / 2.54 cm (16 ft-lbs / in.).

Example 8

To a 11.3 liter (2.5 gal.) Capacity stainless steel first stage vertical reactor equipped with a radial turbine type agitator, pressure sensor and blow-off valve, 6.81 kg of vinyl chloride monomer is added , 1.26 g of dicyclohexyl peroxydicarbonate polymerization initiator sold under the trademark "Lupersol 229", and 0.75 g of a 50% methanol solution of "Gelva" (a densifying agent that is a 2: 1 copolymer of vinyl acetate and crotonic acid is manufactured by Monsanto Co.) · Approximately 0.908Iq * vinyl chloride monomer is vented from the reactor to remove trapped air. The reaction mass is heated to about 70 ° under an autogenous reaction pressure of about 11.8 atmospheres (167 psig) with the stirrer operating at about 1500 rpm. At these temperature and pressure conditions, the mixture is stirred for about 25 minutes. Thereafter, the conversion of vinyl chloride to vinyl chloride polymer is about 8% and the reaction mixture is ready for transfer to the second stage reactor as described below.

In the meantime, add to the second stage reactor, which is a 18.9 liter (5 gal.) Stainless steel reactor, the one with a spiral agitator operating at a speed of about 63 rpm, a pressure sensor and a blow-off valve, at 0 ° 408.63 g Epsyn 40A (an ethylene-propylene-modified terpolymer with a weight average molecular weight of about 160,000, the ethylene-propylene ratio being about 55/45 and

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as diene is ethylidene-norbornene in an amount of 3 + 0.5 $, manufactured by Copolymer Corp.) which has been finely divided and dusted with 58.38 g of powdered, bulk polymerized vinyl chloride polymer (for the prevention of agglomeration and for Ease of dissolution of the polyolefin in the reaction mixture) and 0.4 g of 2,6-di-tert-butylparacresol antioxidant color stabilizer. The mixture is de-aired by applying a vacuum of approximately 73.7 cm (29 in.) Of mercury to the reaction vessel and then the reaction vessel is filled with nitrogen. After repeating the de-air treatment, 3.75 g of "Lupersol 229" initiator and about 7.72 kg of additional vinyl chloride monomer are charged into the reactor to obtain a polyolefin content of about 3% based on the monomer. After the reactor has been closed, the reaction mixture is heated to about 40 ° with stirring and the reaction mixture from the first stage, which has been described above, is added. The reaction mass is then held at a reaction temperature of about 58 at an autogenous pressure of about 9.1 atmospheres (130 psig) for about 2 hours to reach the thick paste state of the polymerization reaction. About 4.54 kg of vinyl chloride monomer are then blown from the stirred reaction mixture over the course of about 40 minutes. An effective polyolefin concentration of 4.5 ° ^ is obtained with the pressure and temperature in the reactor dropping to about 6.3 atmospheres (90 psig) and about 47 °, respectively, during the blow-off reaction. After the blowdown reaction is complete, the stirred reaction mixture is heated to a temperature of about 58 ° over 35 minutes, while a pressure of about 9.1 atmospheres (130 psig) is achieved. Under these latter temperature and pressure conditions, heating is carried out for about 40 minutes. Towards the end of this period of time, a drop in pressure in the reactor indicates that the polymerization reaction is essentially complete. The reactor is heated to about 70 ° and any unreacted vinyl chloride monomer in the reactor is vented over 45 minutes. So that the vinyl chloride monomer residue out of the product as much as possible

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-Each- 27Q168Q

is removed, the product is in vacuo for about 4 h at 85 ° and then about
taken from the reactor.

and then degassed for about 1 hour at about 0 ° and then off

A powdery polymer product with very good impact resistance is obtained in a yield of about 7.36 kg (corresponding to a conversion of monomer to polymer of about 77%, based on that initiated for the polymerization Monomer, the monomer that was blown off during the thick paste state in the second reaction stage, is not included). About 90.1% of the product goes through a 2.0 mm (10 mesh) sieve (U.S. Standard Sieve Series) through it. The latter part of the product contains only about 47 ppm residual vinyl chloride monomer.

Example 9 (comparison)

The procedure is repeated essentially as described except that the amounts of vinyl halide monomer and initiator added at the beginning of the second stage reaction are 3.18 kg and 5.0 g, respectively. aside from that if the monomer removal step according to the invention is omitted, so that the proportion of polyolefin, based on the monomer in the second stage, is essentially the same as in Example 8 above, following the monomer removal step, i.e. about 4.5%. The product, which has a satisfactory impact resistance, is found in a yield of 7.72 kg obtained (corresponding to a conversion of monomer to polymer of> about 80%, based on that added to the polymerization Monomer). Only about 60% of the product pass through the sieve described in Example 8 with a clear mesh size 2.0 mm through. The amount of residual vinyl chloride monomer in the product fraction passed through a sieve with a clear mesh size of 2.0 mm passes through, is about 900 ppm. A comparison of the results of this example with those of Example 8 explained above that the inventive

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- ■ *? - 27Q1680

The process gives a substantial improvement in the resulting small size product particle level and a substantial reduction in the residual vinyl chloride monomer therein even when, as shown in Example 8, the effective concentration of polyolefin after the monomer removal step is substantially below the preferred value of is above about 5.3% .

From the preceding Examples 1, 3 to 5, 7 and 8, which illustrate the present invention, it is evident that many process changes can be carried out in the process according to the invention. For example, if desired, a portion, about 10 percent, of the vinyl chloride reactant can be replaced with a compatible comonomer such as methyl acrylate to provide an excellent, finely divided, particulate vinyl chloride-methyl acrylate polyolefin polymer. It is also advantageous that vinyl chloride which can escape in the aforementioned examples is collected by directing the blown vinyl chloride into a cooled receiving vessel at atmospheric pressure or into a compressor for the liquefaction. The resulting, isolated vinyl chloride can be used for the subsequent polymerization. Furthermore, very good results are obtained in the examples described above when the ethylene, propylene and polyolefin reactants are replaced by the following olefin polymers: polyethylene, polypropylene and ethylene-propylon-diene-modified terpolymer with an ethylene / propylene ratio of 55/45, containing 1,4-hexadiene as diene in an amount of 3 + 0.5%, a 1-butene-ethylene-co-polymer containing 5% ethylene and chlorinated polyethylene, sold under the trademark "Tyrin" will.

Furthermore, instead of adding the polyolefin directly to the polymerization, as in the above examples described, admits that the polyolefin with the entire or,

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- 270168Q

preferably, mix a portion of the vinyl halide monomer reactant and dissolve, partially dissolve or disperse in the monomer with heating and / or stirring as required, prior to addition to the reactor. Although, according to the invention, the addition of the polyolefin to the polymerization reaction mixture can take place at the beginning of the polymerization reaction, ie when the above weight conversion of monomer to polymer has occurred, it is preferred that the polyolefin is added immediately after some of the monomer, for example up to about 20%. , has been converted into the polymer, preferably after about 1 to about 15%, more preferably about 3 to 15%, conversion of the monomer to the polymer. When the polymerization is carried out by the two-stage process in accordance with the previously described processes in GB-PS 1,047,489 and US-PS 3,522,227, the polyolefin is added to the polymerization essentially immediately after the first stage is complete , that is, after preferably about 3 to 15 wt.%, and more preferably, about 7 to about 15 Gevr.% of the monomers are converted into the polymer. Conveniently, when carrying out the polymerization as a two-stage reaction, the polyolefin is added to the second stage so that it is present in the second stage reactor before any substantial polymerization takes place therein.

The addition of the polyolefin reactant following initiation of the polymerization, as described above, along with the monomer blow-off process of the present invention generally results in a faster polymerization reaction, one lower concentration of residual vinyl halide monomer in the polymerization product and especially excellent Distribution of the product particle size, i.e. the product is characterized by a particularly narrow distribution of the product particle size and contains a particularly large, generally predominant fraction of the very smallest particles. Such improved product particle size distribution is of particular note

60 <) 8 2 2/0497

Advantage in many uses of the product, such as injection molding and the extrusion of objects such as pipes or pipelines and tracks or side walls or plates.

According to a further, preferred embodiment of the present invention, it is preferred in the Carrying out the above-described two-stage polymerization for the first reaction stage only part of the or the to add monomers used in the process, the remainder being added so that it can be used in the second reaction stage is present in the thick paste state before blowing off, wherein, in the two-stage process, the blow-off is carried out in the second reaction stage. Generally v / ground at least about 50% by weight or more of monomeric reactant (corresponding to at least about 60% by weight or more of the monomeric reactant when the amount of monomer blown off in the thick paste state of the amount of monomer used in the polymerization is withdrawn) added to the reaction stage of the first stage, the remainder at about the beginning of the second reaction stage is added (so that it is present before the inventive Blow-off procedure is carried out). About 50 to about 60 percent by weight of the monomeric reactant is preferred added in the first reaction stage (corresponding to an addition from about 60 to about 70% of the monomeric reactant, if the monomeric reactant, is blown off is deducted as described above).

This preferred embodiment for the addition of the monomer or monomers when carrying out those described above two-stage polymerization allows the use of a reactor of smaller size as compared to the first stage with the reactor used in the second reaction stage and also the production of a product activated with very good particle size distribution.

809022/04 97

Claims (69)

Claims A process for producing a vinyl halide polymers by bulk polymerization of a vinyl halide monomers in liquid phase, either alone or together with up to about 50 wt.% Of another ethylenically unsaturated monomer copolymerizable therewith in the early presence of more than about 1.8 Gew.J ₀ , based on the vinyl halide monomer, a polyolefin or mixture of polyolefins having a weight average molecular weight of at least about 50,000, characterized in that from the polymerization mass during their thick paste state about 2 wt.% to less than about 50 wt.% of to vinyl halide added to the polymerization mass, the effective concentration of polyolefin or mixtures of polyolefins after vinyl halide removal being over about 3.5% by weight, based on the vinyl halide remaining in the polymerization mass, after removal of the vinyl halide, v / obei finely distributed it is obtained, particulate product with high impact resistance. 2. The method according to claim 1, characterized in that the polymer is a vinyl halide homopolymer, the polymerization is carried out in a single stage and the polyolefin is selected from the group consisting of: (1) halogenated polyolefins, (2) olefin homopolymers, (3) olefin copolymer and terpolymer, the polymers having 2 to 8 carbon atoms in their monomeric units and a weight average Have molecular weights of about 150,000 to 1,000,000 and the amount of vinyl halide monomer removed about 5 up to about 40%, based on that fed to the polymerization Vinyl halide monomer. 809822/0497 ORIGINAL INSPECTED 3. The method according to claim 2, characterized in that the initial concentration of polyolefin or the Geraisch from polyolefins at least about 3 Gew.Jä, based on the Vinyl halide monomer, and that is the effective concentration of the polyolefin or the mixture of polyolefins after removal of the vinyl halide over about 5.3% by weight, based on the vinyl halide remaining in the polymerization composition after removal of the vinyl halide. 4. The method according to claim 3, characterized in that the vinyl halide monomer is a vinyl chloride, the polymerization ale single-stage bulk polymerization at a temperature of about 25 to about 90 ° C. under at least autogenous superatmospheric pressure in the presence of an initiating amount of a free radical initiator for the reaction , the thick paste state of the polymerization mass has a conversion of vinyl chloride to polymer of about 30 to corresponds to about 40% by weight and that about 8 to 35% by weight of vinyl chloride are removed by blowing off from the pressurized polymerization mass and that the polyolefin terpolymers contain a diene as a monomeric unit. 5. The method according to claim 4, characterized in that the vinyl chloride from the polymerization mass in one rate from about 0.1 to 1.5 wt.% vinyl chloride / min, based on the vinyl chloride fed to the polymerization is blown off, the polymerization temperature is about 40 to about 80 ° at autogenous superatmospheric pressure is the diene of the polyolefin terpolymer from the group of dicyclopentadiene, 1,3-butadiene and non-conjugated dienes with linear or cyclic ones Chains is selected and in the terpolymer in a proportion of up to about 15% by weight, based on the terpolymer, is present, and that the effective concentration of polyolefin in the Polymerisatior.ömasee about 5.5 to about 10 wt.%. 809822/0497 2701630 6. The method according to claim 5, characterized in that the diene of the polyolefin terpolymer in the terpolymer in a ratio of up to about 6% by weight, based on the terpolymer, is available. 7. The method according to claim 6, characterized in that the polymerization ^{temperature is about 50 to about 75 0} C, the initiator is an organic peroxy or azo compound which is added to the polymerization mass in a concentration of about 0.01 to about 1, 0%, based on the weight of the vinyl chloride, is added, the effective concentration of polyolefin is about 6 to about 9% by weight, based on the vinyl chloride, and the vinyl chloride from the polymerization mixture at a rate of about 0.15 to 1, 2% / min is blown off, the blowing off starting about 5 to about 15 minutes after the start of the thick paste state in the polymerization mass. 8. The method according to claim 7, characterized in that the weight average molecular weight of the polyolefin is about 150,000 to about 400,000, an organic peroxide is used as the initiator and the vinyl chloride is used the polymerization mixture is vented at a rate of about 0.3 to about 1.2% / min. 9. The method according to claim 8, characterized in that an olefin copolymer as the polyolefin reactant or terpolymer is used. 10. The method according to claim 9 »characterized in that the polyolefin is an ethylene-propylene-ethylidene norbornene terpolymer is. 809822/0497 11. The method according to claim 9, characterized in that the polyolefin is an ethylene-propylene-1,4-hexadiene terpolymer is. 12. The method according to claim 9, characterized in that the polyolefin is an ethylene-propylene copolymer. 13. Method according to claim 9, characterized in that that the polyolefin is a butene-1-ethylene copolymer. 14. The method according to claim 8, characterized in that the polyolefin is an olefin homopolymer. 15. The method according to claim 14, characterized in that the olefin homopolymer is polyethylene. 16. The method according to claim 14, characterized in that that the olefin homopolymer is polypropylene. 17. The method according to claim 8, characterized in that the polyolefin is a halogenated polyolefin. 18. The method according to claim 17, characterized in that the halogenated polyolefin is chlorinated polyethylene. 19. The method according to claim 1, characterized in that that the polymerization is carried out in a first stage in which the reaction mixture is subjected to high-speed stirring is subjected until about 3 to about 20% by weight of the monomer or monomers are converted into polymers and the resulting Reaction mixture polymerized together with one or more additional monomers in a second stage, while which the reaction mixture is stirred at low speed until the polymerization is complete so that the thick paste state of the polymerization in the second 809822/0497 Stage occurs and the removal of the vinyl halide takes place in the second stage. 20. The method according to claim 19, characterized in that a proportion which is at least about 50 wt.% Des or the monomers added to the polymerization reaction is added at the first stage, and the The remainder of the monomer or monomers is added approximately at the beginning of the second stage. 21. The method according to claim 20, characterized in that in the first stage about 50 to about 60 wt. % Of the monomer or monomers that are added to the Polymerisationsredc tion are added. 22. The method according to claim 21, characterized in that about 3 to about 15 wt.% Of the monomer or monomers in the first reaction stage are converted into polymer. 23. The method according to claim 22, characterized in that about 7 to about 15So of the monomer or monomers in the first Stage are converted into polymer. 24. The method according to claim 23, characterized in that that vinyl chloride is used as the monomer reactant. 25, V _e rfahren for producing a vinyl halide polymers by bulk polymerization of a vinyl halide monomers in liquid phase, either alone or together with up to about 50 wt.% Of another ethylenically unsaturated monomer copolymerizable therewith, at initial presence of more than about 1.8 % By weight, based on the vinyl halo genidmonomer, a polyolefin or a mixture of polyolefins having a weight average molecular weight of at least about 50,000, wherein the polyolefin or the 809822/0497 ^M - Mix of polyolefins during the polymerization is only present during the time that begins at 0 to about 20? 6 conversion of the monomer (s) to polymer and ends with the end of the polymerization, characterized in that the polymerization mass is obtained during its thick paste state about 2 to less than about 50 wt.% vinyl halide, which has been supplied to the polymerization mass is removed, wherein the effective concentration of the polyolefin or mixture of polyolefins by the Vinylhalogenidentfernung about 3 »5 wt.%, based on the in the polymerization mass vinyl halide remaining after removal of the vinyl halide, a more finely divided, particulate product having high impact resistance being obtained. 26. The method according to claim 25, characterized in that the polymer is a vinyl halide homopolymer, the polymerization is carried out in a single stage and the polyolefin from the group (1) halogenated polyolefins (2) olefin homopolymers (3) olefin copolymers and terpolymers is selected, Avobei the polymers 2 to 8 carbon atoms contained in their monomeric units and have a weight average molecular weight of about 50,000 to 1,000,000 and the amount of vinyl halide monomer removed is about 5 to about 40% based on that of the polymerization mass added vinyl halide monomer. 27. The method according to claim 26, characterized in that the olefin polymer is present in the polymerization after about VA of the monomer or monomers has been converted into polymer. 809822/0497 28. The method according to claim 27, characterized in that the olefin polymer is present in the polymerization mass is after about 3 to about 15% by weight of the monomers have been converted to polymer. 29. The method according to claim 28, characterized in that the initial concentration of polyolefin or the mixture of polyolefins is at least about 3 weight percent based on the vinyl halide monomer and that is the effective concentration of polyolefin or the mixture of polyolefins after the vinyl halide removal over about 5.3 wt. So, based on the vinyl halide remaining in the polymerization mass after the vinyl halide removal. . 30. The method according to claim 29, characterized in that the vinyl halide monomer is a vinyl chloride, the polymerization is a one-stage bulk polymerization which is carried out at a temperature of about 25 to about 9O ⁰ C under at least autogenous superatmospheric pressure in the presence of an initiating amount of a free radical initiator for the reaction is carried out, the thick paste state of the polymerization mass corresponds to a conversion of vinyl chloride to polymer of about 30 to about 40% by weight and about 8 to about 35% by weight of vinyl chloride are removed by blowing off the pressurized polymerization mass and that the Polyolefin terpolymers contain a diene as a monomeric unit. 31. The method according to claim 30, characterized in that the vinyl chloride is blown off from the polymerization mass at a rate of about 0.1 to 1.5 wt.% Vinyl chloride / min, based on the vinyl chloride fed to the polymerization, the polymerization temperature about 40 to about 80 ⁰ C, the diene of the polyolefin terpolymer is at autogenous superatmospheric pressure, from the group of dicyclopentadiene, 1,3-butadiene and non-conjugated diene is selected with linear or cyclic chains and in the terpolymer 809822/0497 in a ratio or proportion of up to about 15% by weight on the terpolymer, and that the effective concentration of polyolefin in the polymerization mass is about 5.5 to about 10 wt.%. 32. The method according to claim 31, characterized in that the diene of the polyolefin terpolymer in the terpolymer in a relation bz \ /. Share up to about 6% by weight, based on on the terpolymer. 33. The method according to claim 32, characterized in that the polymerization temperature is about 50 to about 75 ° C, the initiator is an organic peroxy or azo compound which is added to the polymerization mass in a concentration from about 0.01 to about 1.0 6 by weight of the vinyl chloride is added, the effective concentration of polyolefin about 6 to about 9 SS weight, based on vinyl chloride, and the vinyl chloride is blown from the polymerization mixture at a rate of about 0.15 to 1.2% / min starting from about 5 to about 15 minutes after the start of the thick paste state in the polymerization begins. 34. The method according to claim 33, characterized in that that an organic peroxide is used as initiator and that the vinyl chloride from the polymerization mixture in a Blow off rate of about 0.3 to about 1.2% / min. 35. The method according to claim 34, characterized in that that the polyolefin is an olefin copolymer or terpolymer. 36. The method according to claim 35, characterized in that the polyolefin is an ethylene-propylene-ethylidene norbornene terpolymer is. 809822/0497 37. The method according to claim 35, characterized in that the polyolefin is an ethylene-propylene-1,4-hexadiene terpolymer is. 38. The method according to claim 35, characterized in that the polyolefin is an ethylene-propylene copolymer. 39. The method according to claim 35, characterized in that that the polyolefin is a butene-1-ethylene copolymer. AO. Method according to claim 34, characterized in that that the polyolefin is an olefin horopolymer. 41. The method according to claim 40, characterized in that that the olefin homopolymer is polyethylene. 42. The method according to claim 40, characterized in that that the olefin horopolymer is polypropylene. 43. The method according to claim 34, characterized in that the halogenated polyolefin is chlorinated polyolefin. 44. The method according to claim 43, characterized in that the halogenated polyolefin is chlorinated polyethylene. 45. The method according to claim 25, characterized in that the polymerization is carried out in a first stage, wherein the reaction mixture is stirred or agitated at high speed until about 3 to about 20% by weight of the Monomers are converted into polymer, and further the resulting Reaction mixture together with one or more additional ones Monomers polymerized in a second stage, during which the reaction mixture at low speed is stirred or moved until the polymerization is complete, the polyolefin or the mixture of polyolefins to the 809822/0497 Reaction mixture was added at the beginning of the second reaction stage becomes that the thick paste state of the polymerization takes place in the second reaction stage and the removal of vinyl halide therefrom in a second reaction stage takes place. 46. The method according to claim 45, characterized in that a proportion which is at least about 50 % by weight of the monomer or monomers added to the polymerization mass is added in the first stage, the remainder of the monomer or monomers being added approximately at The beginning of the second stage is added. 47. The method according to claim 45, characterized in that in the first stage about 50 to about 60 wt.% Of the or of the monomers to be added to the polymerization mass. 48. The method according to claim 47, characterized in that about 3 to about 15 % by weight of the monomer or monomers are converted into polymer in the first reaction stage. 49. The method according to claim 48, characterized in that about 7 to about 15% of the monomer or monomers in the first Reaction stage are converted into polymer. 50. The method according to claim 49, characterized in that the monomer reactant is vinyl chloride. 51. The method according to claim 26, characterized in that that is the weight average molecular weight of the polyolefin reactant is about 50,000 to about 150,000. 52. The method according to claim 26, characterized in that the weight average molecular weight of the poly 809822/0497 1Ί olefin reactant about 150,000 to about 1,000,000 amounts to. 53 Process for the preparation of a vinyl halide polymer by polymerization in the bulk of a vinyl halide monomer in the liquid phase either alone or together with up to about 50% by weight of another, ethylenically unsaturated monomer copolymerizable therewith in the initial presence of more than about 1.8% by weight .%, based on the vinyl halide monomer, a polyolefin or a mixture of polyolefins having a weight average molecular weight of at least about 50,000, the polyolefin or the mixture of polyolefins being present during the polymerization only during the time which is at about 0 to about 20? £ strength conversion of monomer to polymer begins and ends with the end of the polymerization, wherein the polymerization is carried out in a first stage, wherein the reaction mixture is stirred at high speed to about 3 to about 20 wt.% of the monomer or monomers are converted into polymer, and where the resulting reac tion mixture is further polymerized together with one or more additional monomers in a second stage, during which the reaction mixture is stirred at low speed until the polymerization is complete, characterized in that from the polymerization mass during its thick paste state about 2 to less than about 50% by weight of the vinyl halides fed to the polymerization mass, the effective concentration of the polyolefin or the mixture of polyolefins after the vinyl halide removal being over about 3.5 Gevr. %, based on the vinyl halide remaining in the polymerization composition after the vinyl halide removal, a more finely divided, particulate product having high impact strength being obtained. 809822/0497 54. High impact polyvinyl halide, made according to the method of claim 1. 55. High impact polyvinyl halide, made according to the method of claim 25. 56. High impact polyvinyl halide made by the method of claim 53. 57. Process for the preparation of a vinyl halide polymer by polymerization in the liquid phase of a vinyl halide monomer either alone or together with up to about 50% by weight of another, ethylenically unsaturated, monomers copolymerizable therewith in the initial presence greater than about 3.5 weight percent based on the vinyl halide monomer, a polyolefin or a mixture of polyolefins having a weight average molecular weight of at least about 50,000, characterized in that one from the polymerization during from about 2 to less than 50 wt. 96 of their thick paste state of the vinyl halide added to the polymerization mass, being the effective concentration of the polyolefin after vinyl halide removal over about 5.3% by weight, based on that in the polymerization mass after vinyl halide removal remaining vinyl halide, being a more dispersed, particulate product with high Impact resistance is obtained. 58. The method according to claim 57, characterized in that the polymer is a vinyl halide homopolymer, the polymerization is carried out in a single stage and the polyolefin from the group (1) halogenated polyolefins (2) olefin homopolymers 809822/0497 " 27Q1680 (3) olefin copolymers and terpolymers is selected, the polymers containing 2 to 8 carbon atoms in their monomeric units and having a weight average molecular weight of about 150,000 to 1,000,000 and the amount of vinyl halide monomer removed from about 5 to about 30%, based on the vinyl halide monomer added to the polymerization mass, amounts to. 59. The method according to claim 58, characterized in that the vinyl halide monomer is vinyl chloride, the polymerization is a one-stage bulk polymerization which is carried out at a temperature of about 25 to about 90 ⁰ C under at least autogenous superatmospheric pressure in the presence of an initiating amount of a free radical initiator for the Reaction is carried out, the thick paste state of the polymerization mass corresponds to a conversion of vinyl chloride to polymer of about 30 to about 40% by weight and about 8 to 25% by weight of vinyl chloride are removed from the pressurized polymerization mass and the polyolefin polymer is a diene monomeric unit included. 60. The method according to claim 59, characterized in that the vinyl chloride is blown out of the polymerization mass at a rate of about 0.1 to 1.5 wt. 6 vinyl chloride / min, based on the vinyl chloride added to the polymerization mass, the polymerization temperature is about 40 to about 80 ⁰ C at autogenous, superatmospheric pressure, the diene of the polyolefin polymer from the group dicyclopentadiene, 1,3-butadiene and non-conjugated dienes with linear or cyclic chains is selected and in the terpolymer in a proportion of up to about 6 wt .%, based on the terpolymer, is present and the effective concentration of polyolefin in the polymerization composition is about 5.5 to about 10 wt. 809822/0497 61. The method according to claim 60, characterized in that the polyolefin is selected from the group of ethylene-propylene copolymers, ethylene-propylene-diene-modified terpolymers, propylene homopolymers, butane-1-ethylene copolymers and chlorinated polyolefins, the polymerization temperature is about 50 to about 75 ⁰ C, the initiator is an organic peroxy or azo compound, which is added to the polymerization mass in a concentration of about 0 _f 01 to about 1.0? 6, based on the weight of the vinyl chloride, the effective concentration of polyolefin is about 6 to about 8% by weight, based on the vinyl chloride, and the vinyl chloride is blown from the polymerization mixture at a rate of about 0.15 to 1.2% / min begins until about 15 minutes after the start of the thick paste state in the polymerization mass. 62. The method according to claim 61, characterized in that that the weight average molecular weight of the polyolefin is about .150,000 to about 400,000, the initiator is an organic peroxide and the vinyl chloride is removed from the polymerization mixture at a rate of about 0.8 to about 1.0 # / min is blown off. 63. The method according to claim 62, characterized in that the polyolefin is an ethylene-propylene-ethylidene norboraene terpolymer is. 64. The method according to claim 62, characterized in that that the polyolefin is an ethylene-propylene-1,4-hexadiene terpolymer is. 65. The method according to claim 62, characterized in that the polyolefin is an ethylene-propylene copolymer. 809822/0497 66. High impact polyvinyl halide of improved small particle size made by the method of US Pat Claim 57. 67. The method according to claim 57, characterized in that polymerized in zv / ei stages v / ird, during the first Stage the reaction mixture is stirred at high speed until about 3 to about 20 wt.? 6 of the monomer or monomers are converted into polymers, and the resulting reaction mixture together with one or more additional monomers polymerizing is continued in a second stage, during which the reaction mixture is stirred at low speed until the polymerization is completed, so that the thick paste state of the polymerization and the removal of the vinyl halide take place therefrom in the second reaction stage. 68. The method according to claim 45, characterized in that the olefin polymer to the polymerization reaction in the Mixture with a portion of the monomer or monomers used in the polymerization reaction is added. 69. The method according to claim 68, characterized in that that about 6056 of the monomer or monomers involved in the polymerization are added at the first stage, with the remainder being added at about the beginning of the second stage will. 809822/0497