JP2002506482A - Polyvinyl chloride, method for producing the same, and composition containing the same - Google Patents

Abstract

  (57) [Summary] (Co) polymerization of polyvinyl chloride in the presence of an alkyl sulphate or an alkyl sulphate mixture in which at least 30%, preferably at least 50%, of the polyvinyl chloride paste and plastisol with good cell-forming properties and low viscosity are branched Made from resin produced by letting Alternatively, the branched alkyl sulfate or mixture can be blended with the polymer after polymerization.

Description

DETAILED DESCRIPTION OF THE INVENTION         Polyvinyl chloride, method for producing the same, and composition containing the same     Field of the invention   The present invention relates to polyvinyl chloride (hereinafter "PVC"), a method for producing the same, and a process comprising the same. Composition. In particular, the invention relates to a PVC-containing paste with improved properties Or the production of plastisols.     Conventional technology   Pastes or plastisols may be used for floor and wall coverings, artificial leather or leather cloth, soft Used in the manufacture of a wide range of products, including quality molded parts and dipped articles such as protective gloves ing. The paste or plastisol is pulverized to a powder after spray drying. PVC homopolymer latex, which is mixed with a plasticizer to form a paste It is usually manufactured from The PVC latex itself is usually prepared by an emulsion polymerization method and a microphone. It is produced by a suspension polymerization method or a mini-emulsion polymerization method. Pe Rust and plastisol are obtained by polymerizing vinyl chloride with copolymerizable monomers. It can also be made from a PVC copolymer made by As an example of the latter, Vinyl ester, acrylate ester, vinylidene chloride and acrylonitrile Toril. The comonomer is based on the sum of vinyl chloride and comonomer. And up to 40% by weight, preferably from 10% to 30%. Good. Particularly useful copolymers contain vinyl acetate in amounts up to 20% by weight.   Emulsion polymerization is carried out, inter alia, in the presence of a suitable emulsifier. This emulsifier has It has two roles, one of which is (i) the emulsifier is not able to stabilize the polymer particles Is required for an industrially acceptable processing method. One is (ii) where the polymer is isolated by drying, as in the case of PVC , Since the emulsifier remains in the final product, the plastisol produced later This will affect the characteristics.   The literature describes many classes of both nonionic and anionic emulsifiers . As anionic emulsifiers, alkyl carboxylate, alkyl sulfate, alkyl Sulfonates, alkylaryl sulfonates, and sulfosuccinic acid salts You. All of these molecules must have a specific structure to be effective as an emulsifier. The parent (usually a carboxyl or sulfate group) Must have an aqueous tip and a hydrophobic end (which is the organic part of the molecule) Absent. Although such molecules have limited solubility in water, When the concentration exceeds a certain limit (limit micelle concentration), the molecules aggregate and are called micelles. Tend to form loose aggregates, with the hydrophilic tip outside the micelle And the hydrophobic end is located at its internal end (e.g., Cornell University, published in Ithaca, New York in 1953 Recorded on page 204 of the journal (Cornell University Press) The pea that was posted. F. "Polymer Chemistry" by PF Flory Principles of Polymer Chemistry " And the Interscience Publishers, published in New York in 1955 Page 141 of Interscience Publishers F described below. F. Bovey, I. M. Koltov (IM Kolthoff), A. Eye. Medaria (AI Medal) ia), e. Jay. "Emma" by EJ Meehan et al. Emulsion Polymerization ").   Alkyl sulfates have long been recognized and used as emulsifiers, It has been limited only to the class of emulsifiers obtained from alcohols in form.   Alkyl sulfates are generally SO_ThreeProduced by the sulfation of fatty acids using (Long, published by Harlow in 1987) Guman-Science and Technology (Longman Scientific & Techn) acal) ”, pages 157 et seq. of the seventh edition. S. Davidso AS Davidsohn and B.S. Mil with ski (B. Milw idsky) et al., "Synthetic Detergent. s))). In principle, the types of alcohol that can be used as substrates Not limited. The reaction is as follows.       R-CH_Two-OH + SO_Three→ R-CH_Two-O-SO_ThreeH   The alkylsulfuric acid obtained in this way is unstable and hydrolyzes quite rapidly. When it is carried out industrially, for example, in emulsion polymerization Sodium alkyl sulfate which can be used as an emulsifier (chemical structural formula: RC H_Two-O-SO_Three ^-Na⁺) To obtain the final product (usually caustic It is necessary to neutralize immediately. In this reaction, the alkyl group R is That the structure of the system does not undergo any changes, that is, it remains substantially unchanged It is important to note that This is because the chemical structure of the alcohol is derived from it Means to determine the chemical structure of the emulsifier.   Patent applications EP-A-90142, EP-A-108884 and EP-A-1 44614 includes alkyl sulfones having 10 to 20 carbon atoms per molecule. Acid, alkylaryl sulfonic acid or sulfosuccinic acid alkali salt or anne The use of monium salts is disclosed and examples thereof include industrial grade alkanes. Sodium decyl sulfonate, dodecyl sulfonate prepared by sulfation of the mixture Sodium phonate, sodium myristyl sulfonate and their mixtures Have been. The disclosed technology uses a method similar to the "mini-emulsion" described above. Refers to the use of long-chain alcohols. Patent application GB-A-12772 89, potassium alkyl sulfonate for improving the transparency of PVC resin And the use of lithium alkyl sulfonates.   Patent application GB-A-1168920 discloses that a carboxyl group is separated at the α-position. Aliphatic or aromatic, branched and having at least 8 carbon atoms per molecule The use of water-soluble salts of araliphatic saturated monocarboxylic acids as emulsifiers is described. The water-soluble salt avoids unwanted coagulation of the PVC emulsion while Facilitates the production of polymers that are very stable or can be easily thermally stabilized It is stated.   Russian Patent Application No. 181286 describes naphthenic hydrocarbons and paraffinic hydrocarbons. Improves the thermal stability of polymers by sulfonating mixtures with branched chains It has been proposed.   One of the major problems with PVC emulsion technology is that the resulting resin The low viscosity of the paste produced by mixing with an appropriate plasticizer Can be The viscosity of the resulting paste depends on several factors, especially the molecular weight of the polymer. , Polymer particle size distribution, drying conditions, and emulsifiers and other additives present Is affected by the type and amount of   PVC paste is often used in the production of chemical foam products, and the paste is Contains, in addition to other additives, suitable foaming agents which decompose at high temperatures. like this Some of the factors that affect the structure of the resulting paste Is the molecular weight of the polymer, the particle size distribution of the polymer particles, and the emulsifiers present and There are types and amounts of other additives.   In general, it is not impossible to match low paste viscosity with good foamability. But difficult. Polymers that produce very low viscosity pastes are generally poor Medium-sized resin gives very good and fine cell structure while giving cell structure As a result, pastes are usually produced which exhibit high values of viscosity. Regarding the chemical properties of emulsifiers Emulsifiers such as alkylarylsulfonates and sulfosuccinates Gives a poor cell structure at low viscosities, whereas alkyl sulfates have special viscosities. It is used to produce a resin that is not low but has good foaming properties. JP- A-49-111990 includes, for example, a method for emulsion (co) polymerization of vinyl chloride. The use of salts of alkyl sulfates and ethoxylated alkyl sulfates is described. In particular, methyl-branched compounds are mentioned. However, such (common) ) Foams produced from polymers generally have very good properties, while resin The viscosity of the strike is so high that it exceeds the permissible range.     Disclosure of the invention   An object of the present invention is to produce a fine and fine cell structure while maintaining a low viscosity. In a paste or plastisol that can be used to make the structure To provide PVC that can be used.   According to the present invention, with or without a copolymerizable monomer, Consists of polymerizing vinyl chloride monomer in the presence of an emulsifier, Alkyl sulfate may be used as an emulsifier or added to the resulting polymer. And emulsion polymerization, microsuspension polymerization or mini-emulsion A method for polymerizing vinyl chloride by polymerization is provided.   Thus, according to the first aspect of the present invention, a vinyl chloride monomer is Polymerized in the presence of emulsifier, with or without copolymerizable monomer The method of polymerizing vinyl chloride comprises: (i) the emulsifier is at least 30% ( Containing a mixture of alkyl sulfates branched on a molar basis) or ii) the mixture of alkyl sulphates is added to the resulting polymer and The multi-alkylsulfates have the following formula [I]: Where R and R¹Are linear or branched having 1 to 15 carbon atoms An alkyl group and M is a salt-forming element or group; And the branched alkyl sulphates contain from 7 to 20 carbon atoms, It is characterized by the following.   According to a second aspect of the present invention, a vinyl chloride monomer is copolymerized with a copolymerizable monomer. Polymerizing in the presence of an emulsifier, without or with copolymerizable monomers The method of polymerizing vinyl chloride is as follows: (i) at least 30% (on a molar basis) of the emulsifier Containing one or more branched alkyl sulfates, or (i i) the one or more alkyl sulfates are added to the produced polymer; , And each of the above branched alkyl sulfates has the following formula [I]: Where R and R¹Are linear or branched having 2 to 15 carbon atoms An alkyl group and M is a salt-forming element or group; And each of the above branched alkyl sulfates has from 7 to 20 carbon atoms Which is characterized by containing   The present invention provides the above described when used in the polymerization or copolymerization of vinyl chloride monomers. A branched alkyl sulfate represented by the general formula [I] is also provided.   Further, the present invention relates to a method in which a branched alkyl sulfate is added to an emulsifier or Or a plastic produced from PVC produced as an additive and containing a plasticizer Provide C paste or plastisol.     DETAILED DESCRIPTION OF THE INVENTION   The salt-forming element or group M is preferably ammonium or an alkali metal. Sodium is suitable, and the branched alkyl sulfate has 7 to 7 carbon atoms. 18, most preferably 9 to 16. Alkyl groups R and R¹Example Is methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl , And hexyl.   The branched alkyl sulfates used in the method of the present invention have the following formula [II]: Where R and R¹Is as defined above, Can be produced by sulfation of an alcohol represented by   An alcohol of the general formula [II] is converted into an aldehyde according to the following series of reactions. On the other hand, catalytically hydroformylating olefins followed by hydrogenation Therefore, it can also be manufactured.       R-CH = CH-R¹+ CO + H_Two       → R-CH_Two-CH (CHO) -R¹       → R-CH_Two-CH (CH_TwoOH) -R¹ Where R and R¹Is as described above.   Generally, mixtures of different isomers are obtained in this way. A mixture of these May contain variable amounts of the corresponding linear isomer, wherein the linear isomer is Separation can be by physical methods known in the art.   An alcohol having a structure similar to that of the above formula [II] is converted into a short-chain alcohol. Another method consisting of dimerization, the so-called Guerbet process (Eg, in Basel in 1952) Published W .. W. Tailheimer's "Yes Synthetic Methods of Organic   Chemistry), Vol. 6, 736 (p. 270)). in this case, A pure product is obtained. If the substrate is, for example, hexanol, the resulting alcohol Call is where R is pentyl and R¹Corresponds to structure [II] in which is butyl . When the substrate comprises a mixture of short-chain alcohols, the branched A mixture of alcohols is obtained.   The alcohol of formula [II] is then transferred to a sulfation stage, where the alkyl sulfate of formula [I] Produce acid salts.   In a preferred method, the alkyl sulfate is a mixture of alkyl sulfates .   The alkyl sulfates used in the present invention may be completely branched, Alternatively, it may contain a mixture of a linear product and a branched product. The Ideally, the alkyl sulfate is 100% branched, but at least 30%. % (On a molar basis), preferably at least 50% (on a molar basis), most preferably less The object of the present invention is achieved if both of them are branched at 75% (on a molar basis). That is, The linear emulsifier used is different but the pace is faster than resins prepared in the same way. It is possible to obtain resins whose viscosity is significantly reduced. In addition, this kind of milk The cell structure obtained using the PVC paste containing the agent is very good, And significantly worse than the PVC paste containing a linear emulsifier. Absent.   Branched alkyl sulphates are available as seeded variants and And in unseeded variants) "Classic milk (Classical emulsification) polymerization technology, The dispersion is obtained by a high-speed shearing mechanical homogenizer) Loose "micro suspension" and (dispersion of vinyl chloride in water Identification has a role to reduce odor and to stabilize monomer particles against diffusion Is obtained from fatty alcohols). Used in the manufacture of PVC by "emulsions". These three polymerization techniques The techniques are briefly described below, but many modifications of these techniques will be apparent to those skilled in the art. It will be understood that it is known and workable. emulsifier   The polymerization initiator may (optionally) be an oxidizing species (eg, potassium peroxydisulfate), a transition Metal (for example, CuSO_Four), And reduced species (eg, sodium disulfite). Redox system.   First, some of the starting components are charged to the reactor. These include ・ Initial amount of water ・ Optionally, seed latex ・ Potassium persulfate ・ Copper sulfate • Optionally, quantity of emulsifier ・ Other components such as buffers Is included.   After vacuuming the reactor to remove oxygen, the vinyl chloride monomer VCM was (Along with the desired comonomer). After that, set the temperature to the reaction value, Inject salt. The amount of bisulfite added depends on the reaction rate. Start After a certain time (from 0 to 1 hour), it is composed of branched alkyl sulfates The solution of the emulsifier is continuously added to the reactor, and the surface of the polymer particles in the growing process is Stabilize. When the conversion is approximately 70%, the reaction is Through acceleration of the reaction known as the Ruff effect, the conversion reaches 90% to 92% It progresses rapidly until. At this point, residual monomer is exhausted and optional stabilizer is added And the latex is discharged and used in the next stage.   Variants for this method include: Reversing the order of addition of the initiator components, ie reducing agents such as bisulphite Into the reactor and then inject an oxidizing agent such as persulfate; • At first, only a part of the monomer (usually 20% to 25% of the total emission) is charged, From later injection of the remaining monomer during the reaction, either continuously or in several batches Adopting different monomer injection techniques; Applying a mixture of emulsifiers, ie branching emulsifier to another emulsifier And mixing; Apply a different emulsifier to the infusion solution and then use the branched alcohol as an “optional stabilizer” Added at the end of the polymerization or at any stage before drying. When, Is included. Micro suspension   Two reactors are used, a mixing vessel (MV) and a polymerization reactor. The initiator system is oil soluble Oxidizing agents (usually organic peroxides, peresters, peracids, etc.) and transition metal complexes (eg For example, CuSO_Four), Especially reducing agents such as ascorbic acid and bisulfite And an optional water-soluble active system.   Any portion of the VCM (and any comonomer) can be replaced with an amount of water, and any Together with a small amount of a branched alkyl sulfate emulsifier and an oil-soluble initiator (LPO). Add to MV. The MV is stirred for a few minutes. In the meantime, residual monomer, residual Water and CuSO_FourCharge the catalyst into the reactor. Next, the contents of the MV are pumped (Homogenizer), and transferred to the reactor by this pump. Of the emulsifier into very small particles. At the end of this move Heating the mixture to the polymerization temperature and then injecting the activator (ascorbic acid) Be started. Injection rate should be optimized for the reaction rate itself Is adjusted to A few minutes after the start, the solution of the branched alkyl sulfate emulsifier is added to the polymerization mixture. It is continuously added to the compound to stabilize the surface of the growing polymer. Conversion When the rate is approximately 70%, the reaction is known as the Tromsdorf effect. After accelerating the reaction, the reaction proceeds rapidly until the conversion reaches 90% to 92%. At this point, residual monomer is evacuated, optional stabilizer is added, and Is discharged and used in the next stage. Possible variants include: ・ The monomer injection technology described above Use only oil-soluble initiators, even in mixtures, without using any activators To use -All monomers are charged to the MV, for example, complete homogenization Use of multiple different emulsifiers in the MV Apply a different emulsifier to the infusion solution and then use the branched alcohol as an “optional stabilizer” Added at the end of the polymerization or at any stage before drying. When, Is included.   In another microsuspension method, a third component, usually hexadecane, is used as a monomer. And homogenize in the absence of any monomer before adding the monomer. This monomer Causes the particles to swell by a diffusion mechanism. The initiator is redox-based, All of the minutes are water-soluble. Mini emulsion   In this method, a mixture of long chain aliphatic alcohols is mixed with a branched emulsifier. Somewhat diluted (4% -5%) water, optionally in the presence of a polymerization additive such as a buffer Form a solution. Next, the mixture is heated (for example, at 70 ° C. for 2 hours) to form a liquid crystal structure. To form Thereafter, the “emulsifier water” thus formed is transferred to a polymerization vessel, and the Copper oxide and hydrogen peroxide are added, the reactor is evacuated, then VCM and any core Add monomer. The resulting mixture is heated to the reaction temperature before the activator (as Not only corbic acid but also other water-soluble reducing agents). Injection speed is anti It is adjusted to obtain the optimum profile for its own speed.   When the conversion is approximately 70%, the reaction proceeds via the Tromsdorf effect , Proceed rapidly until the conversion reaches 90% to 92%. At this point Is exhausted, the optional stabilizer is added, and the latex is exhausted to Used in stages.   Variants include: ・ The monomer injection technology described above A water-soluble organic peroxide or other water-soluble, activated by a suitable reducing agent Use of inorganic oxidizable species as initiator Use of oil-soluble initiators that are not generally activated Use of long-chain alkanes instead of long-chain aliphatic alcohols Is included.   Variants of all the above-mentioned methods include continuous polymerization methods. The In the polymerization method, the components of the polymerization (water, emulsifier, monomer, initiator, and other additives) are reacted The reactor is continuously charged, and the reaction vessel is connected to a continuous stirred tank reactor (CSTR). Either of the reactors may be used. Continuous emulsion polymerization of vinyl chloride in CSTR is industrial It is known that it is used for. Micro suspension method and Minie The utility of this variant for the marsion method is described in Aizpua et al. rua et. al.) (Macromol. S.). ymp., 111, (1996), page 121).   The branched alkyl sulfate emulsifier has a weight of 3% based on the weight of the vinyl chloride monomer. Suitably it is utilized in the polymerization reaction in amounts up to%. 1 based on VCM Amounts up to% by weight are particularly effective. Branched alkyl sulfates are produced not during polymerization An amount of up to 3% by weight, based on the polymer, when added to the polymer after formation; Suitably, it is added in an amount of up to 1% by weight. Example   The following examples are described for the purpose of illustrating the invention.   The differences in chain length distribution are summarized in the table below as emulsifiers A, B, C and I. Four branched alkyl sulfate emulsifiers were studied.   For testing, MSP (micro suspension) method and ME (mini emulsion) )) Use separate recipes for each of the methods and use the two Different recipes include one or more branched alkyl sulfates and one or more reference sump And another difference is via micro-suspension The latex obtained was blended with a different latex before drying. For reference, three types of alkyl sulfate emulsifiers were used, and one of them (emulsifier D) is a product containing about 20% of branched molecules in our evaluation, The other two are linear products, while one (emulsifier E) has a majority of 12 Consists of a chain of length 10-16, which is ~ 16 carbon atoms, and the other (emulsion Agent F) is a very pure linear product, of which 99% of the chain has 12 carbon atoms Met. Emulsifiers A, B, C and I were prepared by the sulfation of alcohols of formula [II] above. And the alcohols catalytically hydroformylate the corresponding olefin. After the addition of hydrogen to the resulting mixture of aldehydes Was. The results are as follows.* The composite formulation consists of the following components (parts by weight):   PVC 80   PVC filler 20   TiO_Two       5   CaCO_Three     25   Plasticizer 55   Stabilizer 1.5   Blowing agent 3.5 And when using different recipes,   The viscosity of the PVC paste depends on the degree of branching of the emulsifier used, and PVC obtained by highly divergent molecules is obtained by using a linear emulsifier. It can easily be seen that it has a lower viscosity than C.   In another set of experiments performed under slightly different conditions, the formula: C_FourH₉[CH-CH_Two OSO_ThreeNa] C₆H₁₃The pure alkyl sulfate (G) represented by Was used as an emulsifier in microsuspension polymerization. In addition, alkyl Instead of sulfate (G), the following formula:       R^Two[CH-CH_TwoOSO_ThreeNa] R^Three Where R^TwoIs CH_ThreeWhen R^ThreeIs C₉H₁₉And R^TwoIs C_TwoH_FiveWhen R^ThreeIs C₈H₁₇ And R^TwoIs C_ThreeH₇When R^ThreeIs C₇H_FifteenAnd R^TwoIs C_FourH₉When R^ThreeIs C₆H₁₃ And R^TwoIs C_FiveH₁₁When R^ThreeIs C_FiveH₁₁Is, The experiment was repeated using a mixture of alkyl sulfates (H) represented by   From the resulting polymer, using the same composite formulation as described above, The formulation was formulated and the viscosity of the formulation was measured at 20 RPM. Results below Is shown in the table.   These results indicate that the branched alkyl sulfates of the present invention have a substantially linear alkyl Having a viscosity lower than the viscosity of a PVC paste obtained by using sulfuric acid salts It proves that C can be generated.

────────────────────────────────────────────────── ─── Continuation of front page    (81) Designated country EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE), OA (BF, BJ , CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, GM, K E, LS, MW, SD, SL, SZ, UG, ZW), E A (AM, AZ, BY, KG, KZ, MD, RU, TJ , TM), AE, AL, AM, AT, AU, AZ, BA , BB, BG, BR, BY, CA, CH, CN, CU, CZ, DE, DK, EE, ES, FI, GB, GD, G E, GH, GM, HR, HU, ID, IL, IN, IS , JP, KE, KG, KP, KR, KZ, LC, LK, LR, LS, LT, LU, LV, MD, MG, MK, M N, MW, MX, NO, NZ, PL, PT, RO, RU , SD, SE, SG, SI, SK, SL, TJ, TM, TR, TT, UA, UG, US, UZ, VN, YU, Z A, ZW

Claims (1)

[Claims] 1. A vinyl chloride polymerization method comprising polymerizing a vinyl chloride monomer with or without a copolymerizable monomer in the presence of an emulsifier, wherein at least 30% (on a molar basis) of the emulsifier is branched. Or a mixture of the alkyl sulphates added to the resulting polymer and the branched alkyl sulphates are of the following formula [I]: Wherein each of R and R ¹ is a linear or branched alkyl group having 1 to 15 carbon atoms, and M is a salt-forming element or group. A method for polymerizing vinyl chloride, wherein the salts contain 7 to 20 carbon atoms. 2. A vinyl chloride polymerization method comprising polymerizing a vinyl chloride monomer with or without a copolymerizable monomer in the presence of an emulsifier, wherein at least 30% (on a molar basis) of the emulsifier is branched. Containing one or more alkyl sulfates, or the one or more alkyl sulfates are added to the resulting polymer, and the respective branched alkyl sulfates are represented by the following formula [I] : Wherein each of R and R ¹ is a linear or branched alkyl group having 2 to 15 carbon atoms, and M is a salt-forming element or group. The method of polymerizing vinyl chloride, wherein the alkyl sulfate contains from 7 to 20 carbon atoms. 3. 3. The process according to claim 1, wherein the alkyl sulphate (s) is branched by at least 50% (on a molar basis). 4. 4. The method according to claim 1, wherein M is an alkali metal or ammonium. 5. The method according to any of the preceding claims, wherein the branched alkyl sulphate contains 9 to 16 carbon atoms. 6. 6. A process according to claim 1, wherein the branched alkyl sulfate (s) is present in an amount of up to 3% by weight, based on the weight of the vinyl chloride monomer. 7. 3. The branched alkyl sulfate of formula [I] according to claim 1 or 2 when used as an emulsifier for the polymerization or copolymerization of vinyl chloride monomers. 8. 3. The branched alkyl sulfate of formula [I] according to claim 1 or 2 when added to a vinyl chloride polymer or copolymer. 9. A vinyl chloride polymer or copolymer produced by the method of claim 1. 10. A polyvinyl chloride paste containing the vinyl chloride polymer or copolymer according to claim 9 and at least one plasticizer.