CS242180B1 - The production of polyvinyl chloride suspension suspensions - Google Patents

Abstract

Suspension types of polyvinyl chloride are produced by suspension polymerization of vinyl chloride at a temperature of 20-75 °C with initiation by a free-radical initiator, in the presence of dispersants and auxiliaries, while the modifier of the morphology of the PVC powder, ensuring its high porosity and narrow distribution, as well as the modifier of the polymerization process, is a by-product of oxygenated organic production of 2-ethylhexanol by aldolization of butyraldehyde combined with dehydration and hydrogenation, preferably a heavy distillation bottom or a distillation residue from the rectification of 2-ethylhexanol produced by the oxo process. It consists mainly of monohydric and/or dihydric alcohols Cd, Cs and C12, as well as mixtures of esters, ethers, acetals, esters and carbonyl compounds. It is applied in an amount of 0.003-1.0 (0.01-0.1 J wt. % calculated on vinyl chloride.

Description

It has also been found that the suspension types of PVG and bobs are also known. physicochemical and processing properties using as modifiers during the homopolymerization of vinyl chloride, in particular the triorioglycerides, and the distribution of technically-feasible by-products from the petrochemical production of oxygenated organic compounds.

Protective colloids - dispersants that disperse vinyl chloride in an aqueous medium are required for suspension homopolymerization in addition to the injectors. Such dispersants are mainly cellulose derivatives (alkylcellulose, hydroxyalkylcellulose, polyvinyl alcohol, partially saponified polyvinyl acetate, gelatin, maleic anhydride copolymers, polyvinylpyrrolidone and the like). polyhydric alcohols with higher acids, such as glycerol monostearate, glycerol monoricin oleate, alkylarylsulfonates, alkyl sulfates, condensation products of alkyloxiranes with higher fatty alcohols or alcohols. Polivinilchloride, 53—96. Izdatelstvo „Khimija“, Moskva (1968) Other additives are usually oxides, hydroxides as well as metal salts, mainly barium, cadmium, strontium, calcium, magnesium, ol insoluble or only slightly soluble in water and soluble in monomer settling at the phase boundary, also affecting the morphology of the forming polymer.

In addition, antioxidants, pH regulators, molecular weight regulators, or copolymerizations of the comonomer additive, e.g. % vinyl acetate, usually in amounts of 1-4 wt. calculated on vinyl chloride, which have a significant softening effect on PVC-based products.

Last but not least, additives can be applied to prevent clogging of the walls of the autoclaves, stirrers and thermometer wells of the polymers, as well as against the formation of polymeric inhomogeneities, so-called. fisheye mesh.

The disadvantages of the above-mentioned vinyl chloride slurry polymerization modifiers (narrow particle distribution is valuable), but especially the suspension morphology, bulk density and ultimately the processability, high processing productivity and excellent mechanical properties of PVC-based products, are their lower efficiency. , increasing the porosity of the PVC powder produced is a mixture of polyvinyl alcohol with triglycerol monostearate, but in particular a mixture of glycerides or sorbitol laurate (U.S. Pat. No. 210,702; DAS 1,105,616; German Patent 1 245 127 and British Patent 897 370 J. Their sources are limited. condition at room temperature makes handling difficult.

Also useful and effective are polyvinyl alkyl ethers and ethoxylated sorbitan olefins (U.S. Pat. No. 2,886,552), but an additional applicator of the polymerization process and the precipitated slurry can be scrubbed. In contrast, with an aqueous emulsifier system based on 12-18 carbon alkyl or alkenyl phosphate and alkenyl alcoholate (Swiss Patent 635,113), both dispersants and the polymerization regulator can be partially replaced, but a particle morphology modifier is required.

However, a process for the production of suspension types of polyvinyl chloride by suspension homopolymerization of vinyl chloride, at a temperature of 20 to 75 ° C, under the initiating effect of a free-radical initiator or initiators added or added to the reaction medium is disposable or sequentially formed in the reaction medium "in situ"; with the assistance of a dispersant system based on hydroxycelluloses and / or at least partially saponified polyvinyl acetate, polymerization modifiers and / or morphology and particle distribution modifiers of the organic oxygen compound suspension, optionally in the presence of excipients such as molecular weight regulators, pH, environment, antioxidants fillers, additives to prevent the formation of polymeric inhomogeneities and to prevent clogging of walls, stirrers, and autoclave wells, such that the modifier is in a relative amount of 10 and 100% of the total weight of modifiers applied, the absolute amount of 0.003 to 1 wt.%, Preferably 0.01 to 0.1% by weight. calculated on the weight of vinyl chloride, is an oxygen-containing organic product from the production of 2-ethylhexanol by aldolizing butyraldehyde coupled with dehydration and hydrogenation, consisting of 20 to 95 wt. mixtures of aliphatic monovalent and / or divalent alcohols C4 to C12, the remainder being a mixture of saturated and / or unsaturated carbonyl compounds, esters, acetates and ethers, preferably a heavier distillation fraction or a distillation residue from the rectification of 2-ethylhexanol produced by oxoprocessing.

The advantage of the process according to the invention is the technical availability of the modifier, the good efficiency and the very fact that it is at the same time a regulator of both the polymerization process and the particle morphology and particle size. Thus, in technology or in the slurry polymerization recipe, it simultaneously substitutes two components, e.g. oleyl alcohol and sorbitan laurate (Span) or a mixture of mono-, dia-triglycerides of C 17 to C 18 aliphatic acids (Emulsifier C).

The oxygenated crganic product from the production of 2-ethylhexanol by aldolizing butyraldehyde coupled with dehydration and hydrogenation can be obtained as a by-product in the process of producing 2-ethylhexanol, e.g. 2-ethylhexene-1-al-2-ethylhexanol, but mainly in the process of oxosynthesis (propene-n-butyraldehyde + isobutyraldehyde + isobutyraldehyde + isobutyraldehyde + isobutyraldehyde + * butyraldehyde - * butyraldehyde - * butyraldehyde - aldol) aldol (C 2 -ethylhexen-1-al 2-ethylhexanol), consisting mainly of 2-ethylhexanol and dodecanol, further aldols, ie C 8 and C 12 diols, acetals and their decomposed saturated and possibly unsaturated ethers, esters as well as aldehyde C3 to C12, if any.

The modifier of the present invention may be combined with other modifiers.

Further details of the method of the invention as well as other advantages are apparent from the examples.

Example 1

An autoclave of a volume of 5 ^dm3 stainless steel provided with anchor stirrer (180 obr.min ^-1) were weighed 2200 g of distilled water to 0.7 grams of hydroxypropyl methylcellulose (methylcellulose propylénglykoéteru by the name Klucel I, 0.4 g partially of polyvinyl acetate or technical polyvinyl alcohol in the form of an aqueous solution, known under the trade name Slovlol R (manufactured by W. Pieck Chemical Works, np Nováky) approximately of the following composition:

+ 1.5 wt. dry matter, acetate group content 14,5 + 0,8% w / w, acid value 4 mg KOH / g, saponification number 130 + 15 mg KOH / g and average molecular weight 18 000 to

000th

In addition, as a modifier, 0.6 g of a mixture of saturated and unsaturated alcohols C14 to C20 (C14 to C16 = 5% by weight; Cie = 5 to 15% by weight; Cie = 75 to 85% by weight; to C20 = = 5% by weight, water content up to 0.5% by weight, saponification number = max. 4 mg KOH / g; hydroxyl number = 195 to 210; iodine number of Hanus = 80) known under the trade name Hadenol 80 and in quantities 1.5 g of another particle morphology modifier and, in part, also during the polymerization process, also called a secondary dispersant, partially saponified fats, known under the trade name Emulsifier C, respectively. partially esterified glycerol with stearic acid and oleic acid [acid number = 6.6 mg KOH / g; saponification number = 168.1 mg KOH / g; OH - = 5.38% by weight; bromine value = 25.0 g Bn / 100 g). To this is added 2 g of trichlorethylene, 0.1 sodium hydroxide, 0.2 g of 2,6-di-tert-butyl-4-methylphenol, 3.5 g of bis- (4-tert-butylcyclohexyl) percarbonate known under the trade name. Perkadox 1662 F with a peroxide content of 98% by weight. and 3.5 g of dilauroyl peroxide. Finally, after removal of air, 1730 g of vinyl chloride are added. Polymerization at 56 + 0.2 ° C was continued (10 h) until a pressure drop of 0.3 MPa occurred. The conversion of vinyl chloride reaches 89 + 3 ° C and the product is dried at 50 ° C under reduced pressure.

The product obtained has a K value of 66 + L bulk density of 49 + 20 g.dm ^-3 , a thermal stability of 66% and a plasticizer absorption of 8 minutes.

In the second experiment, only a 0.6 g mixture of C14 to C20 unsaturated and saturated alcohols and half, i.e. 0.75 g of partially saponified fats (similar to 1.50 g of heavy distillation residue from 2-ethylhexanol rectification) was used instead of 0.6 g. in the process of oxosynthesis, referred to in short for 2-EHTP of the following analytical characteristic: density at 20 ° C - 882.8 kg.m ^-3 , n _o 20 ₌ 13478, kinematic viscosity at 20 ° C - = 33.6.10 ^-6 m ² s ^-1 , at 50 ° C = 8.25.10 ^-6 m ^and s ^-1 , acid number = 0.57 mg KOH / g saponification number - 29.8 mg KOH / g,

OH = 7.31% by weight,

CHO = 0.2 wt%, bromine number = 2.93 Brz / 100 g, molecular weight - 220 gm ^-1 , pour point - 54 ° C.

The polymerization process, polymer yields, bulk density, K-value and thermal stability are similar to those of the previous case. The absorption of the wetting agent is 7 min.

In a third experiment, the entire modification system (Hadenol and Emulsifier C) was replaced with 2-EHTP in an amount of 2.1 g. The achieved polymerization parameters and the quality of the suspension PVC are similar to those of the previous two experiments, only the absorption of the wetting agent is 9 min.

Example 2

a)

104 kg of demineralized water, 0.044 kg of methylhydroxypropylcellulose (Methocel F-50) in the form of an aqueous solution at a concentration of 2% by weight are charged to a 250 dm ³ stainless steel autoclave equipped with a duplicator, a propeller stirrer and three vertical stops. and 0.022 kg of hydroxypropylcellulose (Klucel I) also in the form of an aqueous solution at a concentration of 2% by weight. Furthermore, 0.013 kg of oleyl alcohol, 0.002 kg of 2,6-di-tert-butyl-p-cresol, 0.095 kg of mixed organic peroxides · (EHP-80) in the form of a 50% by weight xylene solution, 0.020 kg of sodium carbonate in the form of aqueous solution. Thereafter, the autoclave is sealed and inerted by a pressure of 0.4 MPa by triple flushing with nitrogen 11a. Is then added 73 kg of vinyl chloride, and starts the heating with stirring (300 FIG. Min. ^-1) until the Inter-

of a lymerization temperature of 52 ° C. This is maintained to an accuracy of 0.5 ° C. At a pressure drop of 0.3 MPa, the suspension polymerization of vinyl chloride is terminated such that the converted vinyl chloride is degassed. The autoclave is then heated to 80 [deg.] C. and maintained for 30 min. while discharging desorbed residual vinyl chloride. Thereafter, the contents of the autoclave are cooled to 30 ° C and the suspension is treated with demonomerization, centrifugation, optionally with further demonomerization and then drying at 65 ° C. PVC extracts with a free vinyl chloride content below 1, 10 ^-4 % by weight and volatiles below 0.03 wt. reaches about 90%. The K-value of the PVC powder is 71 + +1 (according to CSN 64 3200 j; bulk density 0.52 kg.dnr ³ ; sieve analysis (according to CSN 64 0212): sieve residue 0.25 mm = 0.4 on sieve 0.063 mm = 92.3%, absorption of plasticizer = 25 min.

b)

In the second experiment, a similar but 0.013 kg slurry of oleyl alcohol as a slurry polymerization modifier and partly the morphology of the particles was used using 0.013 kg of the heavy fraction from the production of 2-ethylhexanol by oxosynthesis. (EHTP) has a distillation start at 184 ° C and an end at 285 ° C, after which it distills from a volume of 100 cm ^{3 a} total of 86 cm ^{3 of} distillate:

density at 20 ° C - 905.5 kg.nr ³ , viscosity at 20 ° C = 133.7 mPa.s, water - 0.73% by weight, mixture of at least 10 oxygen-containing organic compounds, saponification number = 20.9 mg KOH / g, acid value = 0.62 mg KOH / g, bromine number = 6.35 Bn / 100 g,

CHO = 0.11% by weight,

Ofi% = 12.15% "by weight., And butýťaldéhýdizóbútýlac 'which ^l t; -' 0.7% 'by weight., 2-etýlhexááol == 23,% D hiňó.t.", "was", and the diol dodecanol' = 4.1% by weight, popbT's 0.01% by weight.

The course of polymerization is identical to that of the first experiment, similar to the K-value, bulk density and sieve analysis, only the absorption of the wetting agent is clearly better, reaching 19 min.

c)

In the third experiment, the procedure is similar to the first, except that 0.013 kg of oleyl alcohol is added as the EHTP modifier 2 specified in the second experiment b) in a total amount of 0.033 g. The polymerization process, the K value of the PVC polymer obtained, the bulk density as well as the sieve analysis, the residual vinyl chloride are similar to those of the first and second experiments, but the absorption of the wetting agent, which reaches 12 min.

d)

In the fourth experiment, instead of 0.013 kg of oleyl alcohol, 0.023 kg of EHTP and 0.010 g of a mixture of mono-, diglycerides and triglycerides of higher fatty acids, respectively, were used as modifier. partially saponified fats (trade name Emulsifier Cj with a melting point of max. 40 ° C, with a monoglyceride content of up to 30% and a water content of less than 1% by weight).

The suspension homopolymerization of vinyl chloride, the K-value of the powder, the bulk density, the sieve analysis and the residual vinyl chloride are similar to those of the previous three experiments except that the absorption of the wetting agent is 11 min.

Claims (2)

242180 lyophilization temperature 52 ° C. This is maintained by 4; 0.5 / 0. With a pressure drop of 0.3 MPa, the suspension polymerization of vinyl chloride is terminated by degassing the Tiesconverted vinyl chloride. The autoclave is then heated to 80 DEG C. for 30 minutes. with simultaneous removal of the desorbed residual vinyl chloride. Thereafter, the autoclave content is cooled to 30 ° C and the suspension is treated by de-erosion, centrifugation, optionally with further demonomerization and then drying at 65 ° C. PVC extracts with free vinyl chloride content below 1.0-4 wt. % of the volatiles below 0.03 wt. reaches 90%. The K-value of PVC powder is 71 ++ 1 (according to ČSN 64 3200 j; bulk density0.52 kg.dur3; screen analysis (according to ČSN64 0212): sieve residue 0.25 mm = 0.4n sieve 0.063 mm = Absorption rate = 25 min b) In a second experiment, a similar procedure was followed, but instead of 0.013 kg of oleyl alcohol modifier for the suspension polymerization and partly the morphology of the particles, a 0.013 kg heavy fraction from the production of 2-ethylhexanol by oxosynthesis was used, (distillation residue of 2-ethylhexanol rectification) (2-EHTP) has a distillation start of 184 ° C and an end temperature of 285 ° C, after which 86 cm 3 of distillate distils from a volume of 100 cm 3: density at 20 ° C - 905.5 kg.nr3, viscosity at 20 ° C = 133.7 mPa.s, water - 0.73% by weight, a mixture of at least 10 oxygenated organic compounds, saponification number = 20.9 mg KOH / g, acid value = 0.62 mg KOH / g, bromine number = 6, 35 Bn / 100 g, CHO = 0.11% w / w, Ofi4 = 12.15 · 48ύηύοί., Boutýřaldéhýdižóbutýlác & 'tál · -' 0.7% w / w, 2-ethylhexalane == '23; %, a mixture of diol and dodecanol = 4 44% by weight, or 0.01% by wt. The course of the polymerization is identical to that of the first experiment, similar to the K-value, bulk density and sieve analysis, only the absorption of the plasticizer is clearly better, reaching 19 min. c) In a third experiment, the procedure is similar to that of the first, but instead of 0.013 kg of oleyl alcohol is added as the modifier 2 EHTP, specified in the second experiment b), in the total amount of 0.033 g. sieve analysis, residual vinyl chloride is similar to the first and second experiments, but the absorption of the plasticizer, which reaches 12 min. d) In a fourth experiment, instead of 0.013 kgoleylalcohol, a modal modifier of 0.023 kg EHTP and 0.010 g of a mixture of monoglycerides, diglycerides and higher fatty acid triglycerides, respectively, are used. partially saponified fats (trade name Emulsifier C] with a melting point of max. 40 ° C, with a content of up to 30% of monoglycerides and a water content below 1% by weight) Slurry homopolymerization, vinyl chloride, K-value, bulk, sieve analysis and residual vinyl chloride is similar to the previous experiments, only the absorption of the wetting agent reaches 11 min., ARTICLE A method for producing suspension types of polyvinyl chloride by suspension homopolymerization at a temperature of 20 to 75 ° C, with the initiation effect of a free radical initiator or initiator, added or added single or post-reactive medium. stepped or formed in the reaction medium "in situ" from the raw materials, further co-acting with a dispersant system based on hydrocelloids and / or at least partially saponified polyvinyl acetate, further modifying the course of polymerization and / or morphol modifiers and the particle distribution of the organic oxygen compound suspension, optionally in the presence of auxiliary agents such as molecular weight regulators, pH environment, antioxidants, fillers, polymeric non-homogeneity additives, np, plant 7, yarn and to prevent clogging of walls, mixers and autoclave wells, characterized in that the modifier is in a relative amount of 10 to 100% of the total weight of the modifiers applied, in an absolute amount of 0.003 to 1.0% by weight, preferably 0.01 to 0.1 ( % wt. based on the weight of vinyl chloride, the most oxygenated organic product from the production of 2-ethylhexanol is the aldolization of butyraldehyde associated with dehydration and hydrogenation, consisting of 20 to 95 wt. a mixture of aliphatic monovalent and / or divalent alcohols (C 4 to C 12), wherein a mixture of saturated and / or unsaturated carbonyl compounds, esters, acetals and ethers, preferably a heavier distillation fraction or a distillation residue from oxoprocess 2-ethylhexanol rectification, . Price 2.40 Kčs