A method of inhibiting the polymerization of vinyl chloride


(57) Abstract:

Usage: inhibition of polymerization of vinyl chloride in the process of its synthesis and distillation. The inventive as inhibitor use nN-bis-/3,5-di-tert-butyl-4-oxybenzyl/piperazine in the amount of 0.025 to 0.2% by weight of vinyl chloride. table 1.

The invention relates to the field of macromolecular chemistry, more specifically to methods for inhibiting the polymerization of vinyl chloride. The problem is particularly relevant in industrial scale for the synthesis of a monomer and its rectification, because in these conditions, there is the formation of polymer, collecting pipes, showerheads, and a plate distillation columns, as well as tube boilers, which reduces the length of the run of the columns.

You know the introduction of the polymerization recipe inhibitors 2,2-methylene or 2,2-ethylidene-bis(4,6-di-tert - butylphenol) [1]

The closest in technical essence to the present invention is a method of inhibiting the polymerization of vinyl chloride in the process of rectification and storage in the presence of inhibitors, representing aromatic oxycoedone type phenol or its alkalinuria, when in the reaction mixture are the real initiators (percarbonate, Monomeric or polymeric peroxide vinyl chloride).

The aim of the invention is to increase the efficiency of inhibition of polymerization in the synthesis and distillation of vinyl chloride (I).

This goal is achieved using the inhibitor N,Nlbis-(3,5-di-tert-butyl-4-oxybenzyl)piperazine (BP), taken in an amount of 0.025 to 0.2 wt. from REF. The product under THE 6-22-166-87 and has the structural formula:

HO - CH2- NN CH2-

N, Nlbis-(3,5-di-tert-butyl-4-oksijen - ZIL)piperazine is a white powder with a melting point 212about(Mass fraction of the basic substance is 97% mass fraction of water and volatile substances 0,5%).

P R I m e R 1-5. In spetsstalej autoclave (4 liters) equipped with a jacket for maintaining the desired temperature and stirrer, load 1550 g of the aqueous phase (0,15% solution of methyl hydroxypropyl in water), consisting of 0.09 g of caustic soda and 0,0089 g of diphenylolpropane; 2.9 g of the initiator di-2-ethylhexylcarbonate and 800 g of vinyl chloride. In the curing composition of the formulation is administered inhibitor of BP in the number 0,025; 0,05; 0,075; 0,1; 0,2% by weight of mono the first change of the amount of pressure from the initial appointment, the duration of polymerization and polymer yield.

The results are presented in the table and show that with increasing concentration of the inhibitor is observed the decrease of the magnitude of R, the increase in time of polymerization and reduction of output PVC. The highest efficiency of product BP is manifested at a concentration of 0.1% by weight of vinyl chloride.

P R I m e R 6 (for comparison). Similar to examples 1-5, but without the introduction of inhibitor. In this case, there is a significant pressure drop, the polymerization ends quickly enough for 6 h, and the polymer yield is at the level of conventional suspension process. The data given in the table.

P R I m e R s 7-9 (for comparison). Similar to examples 1-5, but as inhibitors used respectively hydroquinone (0.1% of I) and BHT (0.1 and 0.4% of BX). The results are shown in the table. It should be noted that the sum of the indicators introduction hydroquinone almost identical to the control sample (example 6). BHT is a more effective inhibitor than hydroquinone, but much inferior to the proposed BP product even in the case of a fourfold increase in concentration (comparison of examples I, as inhibitor use N, N-bis-(3,5-di-tert-butyl-4-oxybenzyl)piperazine in the amount of 0.025 to 0.2% by weight of vinyl chloride.


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FIELD: protective coatings.

SUBSTANCE: composition contains perchlorovinyl resin, titanium dioxide filler, pigment , and solvent, wherein solvent is ethyl acetate or dichloromethane and ethyl acetate, or dichloromethane and acetone.

EFFECT: shortened drying time, simplified composition, and reduced toxicity.

1 tbl

FIELD: chemistry of high-molecular polymers.

SUBSTANCE: invention relates to polyvinyl chloride and its using. Proposed suspension polyvinyl chloride has Fickentcher's constant value Kf = 77-88, and it represents powder consisting of porous unclear particles characterizing the specific surface value 1.0-4.0 m2/g and the porosity value 0.27-0.42, and enhanced chemical stability in organic solvents also. Polyvinyl chloride is prepared by an aqueous-suspension polymerization of the reaction mixture comprising vinyl chloride, stabilizing agent and peroxide initiating agent at average polymerization temperature 35-42° and revolution rate of mixer 0.5-3.5 s-1. Polyvinyl chloride with abovementioned indices is used for making different plasticized materials with improved physical-mechanical indices.

EFFECT: improved and valuable properties of polymer.

3 cl, 2 tbl

FIELD: chemical industry, high-molecular chemistry.

SUBSTANCE: polyvinyl chloride is obtained by vinyl chloride suspension polymerization in presence of oil soluble initiator and stabilizing system containing 0.1 % (based on polyvinyl chloride mass) of 2,6-di-tert-buthyl-4-methylphenol and 0.003-0.006 % mixture of oxyethylated C7-C10-alkylphenols and optionally 0.07-0.35 % of calcium stearate, wherein 2,6-di-tert-buthyl-4-methylphenol is supplied into reaction mixture before vinyl chloride feeding, and mixture of oxyethylated C7-C10-alkylphenols and optionally calcium stearate are added in form of homogenous suspension obtained by blending with water after pressure drop by 0.05-0,1 MPa.

EFFECT: polyvinyl chloride of improver thermal stability and increased environmental and sanitary safety.

10 ex, 1 tbl

FIELD: organic synthesis and polymerization processes.

SUBSTANCE: invention relates to preparation of peroxide vinyl chloride polymerization initiators and comprises initial reaction of mixture of substituted and non-substituted alcohols with phosgene followed by treatment of phosgenation products with sodium peroxide and subsequent isolation of final product, which may be accomplished by adding a solvent such as hexane. Non-substituted alcohols are selected from various fractions of synthetic fatty alcohols and substituted alcohols are selected from ethylene glycol monoethers, synthetic fatty alcohols/ethylene glycol monoethers molar ratio being 1:(.25-4) and molar ratio of phosgene to mixture of alcohols and ethylene glycol monoethers (0.75-1.1):1. Reaction of above mixture with phosgene is conducted at temperature from -10 to 8°C for 2-6 h followed by gradual temperature rise to 40-55°C. Treatment of phosgenation products with sodium peroxide is conducted at temperature from -10 to 5°C and weight ratio of phosgenation products to sodium peroxide (3.5-10):1. Resulting multicomponent initiating modifying system contains initiators and additives providing uniform and high rate of suspension vinyl chloride polymerization to produce polymer with high temperature resistance, high homogeneity of particles regarding granulometric composition, density, and structure, and improved workability.

EFFECT: accelerated suspension polymerization of vinyl chloride and improved characteristics or resulting polymer.

1 dwg, 6 ex

FIELD: chemistry of polymers, chemical technology.

SUBSTANCE: invention relates to a polymerization method of vinyl chloride monomer and optionally additional monomers by using a single or some organic peroxides. This method involves dosing at least one organic peroxide compound with half-time value from 0.0001 h to less 0.050 h at the polymerization point to the polymerization mixture. Dosing such initiating agent allows achievement of improving the polymerization rate regulation and higher rate of polymerization. By using this method vinyl chloride-base (co)polymer is prepared having less 50 mass parts of residual initiating agent per one million of mass parts of (co)polymer in measuring after polymerization and drying (co)polymer at 60°C for 1 h directly. (Co)polymer can be used in the molding process involving heating a (co)polymer to temperature exceeding its boiling point.

EFFECT: improved method for polymerization.

8 cl, 2 tbl

FIELD: chemistry of polymers, chemical technology.

SUBSTANCE: invention relates to a method for polymerization of one or some monomers one of that is vinyl chloride monomer. Method involves addition of the standard system of organic peroxides to polymerization mixture in the first step of polymerization, and one or some of additional organic peroxides and, optionally, surfactant are added to the polymerization mixture at the reaction temperature value when pressure in the polymerization reactor falls due to depletion of vinyl chloride monomer amount. Indicated additional organic peroxides have half-time value less 1 h at the polymerization temperature under condition that formed polymer is not subjected for radio-frequency dielectric heating in the presence of additional organic peroxide. The proposed method provides decreasing the polymerization time owing to higher rate value of the pressure drop in the end the polymerization reaction. Also, invention provides the enhanced effectiveness of cooling capacity of polymerization solution.

EFFECT: improved effectiveness of polymerization process.

5 cl, 1 tbl, 1 ex

FIELD: chemistry and technology of polymers.

SUBSTANCE: invention relates to a method for suspension polymerization of vinyl chloride. The polymerization reaction of vinyl chloride in an aqueous suspension is carried out in the presence of a protective colloid and peroxide initiating agent used in the amount 0.03-0.1% of monomer mass. As a initiating agent method involves using multi-component system comprising the following components, wt.-%: mixture of symmetric and non-symmetric dialkyl peroxydicarbonates, 75-82; synthetic saturated (C5-C22)-alcohols, 1-2.5; alkyl chlorides, 7.5-10; dialkylcarbonates and diethylene glycol esters, 8-14. This composition of mixture provides the constant rate of polymerization of vinyl chloride, uniform heat evolving during all process and creates the possibility for the improved rational using equipment exploited in the polymerization process, significant decreasing auto-acceleration of polymerization in the field of deep conversions, to reduce the process time, to enhance the yield and quality of polymer. All said above results to improvement of thermal stability, granulometric composition, increasing porosity of polyvinyl chloride, its improved capacity for processing and physicochemical properties of synthesized polymeric materials.

EFFECT: improved method for polymerization.

2 cl, 5 tbl, 1 dwg, 21 ex

FIELD: polymer materials.

SUBSTANCE: suspension polyvinylchloride according to invention represents suspension polyvinylchloride with Fickentcher constant = 35-42, which is white powder of nonporous glass-like particles characterized by ratio of Fickentcher constant to "plasticizer absorption time" ranging from 0.3 to 3.0. The powder is prepared via water-suspension polymerization of reaction mixture containing vinyl chloride, peroxide initiator, water, stabilizer, and molecular mass regulator (chlorinated hydrocarbon), which polymerization proceeds on heating and vigorous stirring of reaction mixture (0.5-3.5 s-1) at 60-80°C. Thus obtained polyvinylchloride shows elevated solubility in organic vanish solvents (at least 99%) and finds use in preparation of compositions with elevated aggregative stability in organic vanish solvents useful in production of stable high-concentration varnishes and enamels and containing volatile compounds up to 50%. Polyvinylchloride with indicated characteristics is employed as binder in production of lacquer materials capable of forming coatings with good physicochemical and protective properties. Polyvinylchloride solution itself is characterized by high stability on storage, also at negative temperatures.

EFFECT: extended application area of polyvinylchloride.

5 cl, 2 tbl

FIELD: chemistry.

SUBSTANCE: in the method of obtaining polyvinylchloride through suspension polymerisation of vinylchloride in the presence of a protective colloid, oil-soluble initiator, 2,6-di-tret-butyl-4-methylphenol, Zn-containing or Zn-Mg-containing glycerine monoester based on alpha-branched saturated monocarboxylic acids of the C10-C28 fraction in quantity of 0.03-0.06 wt % of vinylchloride, is added to the reaction mixture before adding vinylchloride. When necessary, with the aim of boosting the thermostabilisation effect, a Ca stearate or Ca-Zn stearate in quantity of 0.03-0.06 wt % of vinylchloride, is added to the reaction mixture before adding the monomer.

EFFECT: obtaining polyvinylchloride with high thermal stability and good melt fluidity, with improved morphological uniformity and, consequently, improved processing properties.

1 tbl

FIELD: chemistry.

SUBSTANCE: proposed here is a polymerisation method of one or more monomers using at most, 90 wt % safe amount of a first initiator. The safe amount of initiator used is the maximum amount of the given initiator, which can be used in an identical method, realised at maximum cooling power, and temperature of which does not exceed a set temperature value. A second initiator is used, with half-life from 0.0001 to 1.0 hours at polymerisation temperature. The second initiator has less thermal stability than the first initiator. 10% monomer(s) are at least partially added before polymerisation, in such a quantity and preferably at a different rate such that, not less than 92% of the maximum cooling power is used, at least, in the period of time, in which not less than 10 wt % monomer is polymerised. The initiators are chosen from organic peroxides and standard azo-initiators.

EFFECT: cheap method of producing polymers, particularly polymers containing polymerised vinylchloride.

9 cl, 2 tbl