JPS61225241A - Production of composite polymer - Google Patents

Abstract

PURPOSE:To obtain a composite polymer having excellent processability, strength, compression set and flexibility, by mixing a particulate vinyl chloride polymer, a nitrile elastomer and a solvent in an aq. medium, removing the solvent and dehydrating and drying the mixture. CONSTITUTION:1-99wt% particulate vinyl chloride polymer (A) having an average particle size of 200mum nitrile elastomer (B) having a nitrile monomer content of 5-80wt% and an iodine value of 120 or below, 30-1,000pts.wt. (per 100pts.wt. component B) solvent (C) (e.g. vinyl chloride) which is incompatible with water and a poor solvent for component A and dissolves component B, and 30-500pts.wt. (per 100pts.wt. of the combined quantity of components A and B) water (D) are mixed at room temp. to 80 deg.C for 30min-3hr. Component C is then removed and the resulting mixture is dehydrated and dried.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a polyvinyl chloride-based polymer (hereinafter sometimes referred to as PVO) and a highly unsaturated nitrile distomer, which has excellent processability, strength properties, and high temperature properties. The present invention relates to a method for producing a granular composite polymer with excellent creep properties and flexibility.

(Prior art) Conventionally, PVC is produced by mixing highly unsaturated acrylonitrile-butadiene copolymer rubber (MBR) with PVC.
By imparting flexibility to VC and improving its compression set, or conversely by mixing PVC into NBH based on highly unsaturated HBR, we can improve the ozone resistance, flex cracking resistance, oil resistance, and resistance of NBH. Attempts have been made to improve wear resistance, workability, etc.

In this case, PVC and highly unsaturated NBR are usually mixed by triblending or latex blending, but since the two are not necessarily uniformly dispersed, the physical properties are often not sufficiently expressed. (9) As the degree of unsaturation of NBR increases, the mass production efficiency decreases, and as the number of unmelted particles increases, the processability deteriorates. Moreover, since the mixtures of both are usually in the form of sheets or pellets, they are difficult to handle with mixing or forming equipment, and therefore more finely divided forms are often required.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a finely dispersed PVC and highly unsaturated nitrile elastomer that has good workability, strength properties, high temperature creep properties (particularly compression set), and flexibility. The objective is to produce an excellent granular composite polymer.

(Another Means to Solve the Problems) This object of the present invention is to obtain granular PVC (AJ, iodine value (
After mixing a nitrile elastomer (B) with a nitrile elastomer (B) having a value of 120 or less (as measured by J.S. KOO70) and a solvent (C) for (B) which is incompatible with water and is a poor solvent in an aqueous medium. , (C) is removed, dehydrated and dried, (
This is achieved by producing a particulate composite polymer consisting of Shu and (E).

The granular PVC used in the present invention includes vinyl chloride homopolymers, vinyl chloride and other monomers copolymerizable therewith (e.g., olefins, vinyl esters, alkyl vinyl ethers, unsaturated carboxylic acids and their esters). copolymers with vinyl chloride and other polymers (e.g., ethylene-vinyl ester copolymers,
Ethylene, -alkyl (meth)acrylate copolymer,
(ethylene-globylene copolymer, polyurethane, etc.)
Examples include graft copolymers with The average particle size is usually 200 μm or less, preferably 150 μm or less. If the particle size exceeds the above range, it is undesirable because the uniformity of the processed product of the obtained composite polymer will be insufficient, the appearance of the product will be deteriorated, and the strength will be reduced.
C may be produced by any method such as emulsion polymerization, suspension polymerization, bulk polymerization, or gas phase polymerization (and its form may be dehydrated, dried, or after the completion of the polymerization reaction). It may be in either slurry or latex form.The degree of polymerization of PVC is usually 300 to 500.
It is 0.

The nitrile elastomer having an iodine value of 120 or less used in the present invention is a copolymer nydistomer of a nitrile monomer and a monomer copolymerizable therewith, or an arbitrary elastomer in which a nitrile group is introduced. In the case of the former nidistomers, the content of nitrile monomers is from 5 to 80% by weight, preferably from 15 to 60% by weight. If the amount of nitrile monomer is less than 5 weights, the resulting composite polymer will not exhibit strength or other physical properties because of poor oil resistance and poor compatibility with PVC. On the other hand, if it exceeds 80% by weight, there is a disadvantage that the resulting composite polymer has poor flexibility. Examples of nitrile monomers include acrylonitrile, methachloronitrile, α-chloroacrylonitrile, α-cyanoethyl acrylonitrile, and vinylidene. Examples include cyanide, maleonitrile, allyl cyanide, etc. Monomers copolymerizable with nitrile monomers include monoolefins such as ethylene, propylene, imbutylene, and butene-1; diolefins such as butadiene, isoprene, chlorogrene, and 1,3-pentadiene; and acrylics. acid, unsaturated acids such as methacrylic acid: methyl of this acid,
Examples include unsaturated acid esters such as alkyl esters such as ethyl, butyl, and 2-ethylhexyl. Two or more of these nitrile monomers and other monomer components may be contained in the copolymer. Such nitrile elastomers are mainly produced by emulsion polymerization or solution polymerization. However, if the iodine value exceeds 120, the unsaturated portion can be removed by a normal hydrogenation method to an iodine value of 120.
It is necessary to do the following. Anything exceeding this value has poor weather resistance, oil resistance, heat resistance, cold resistance, etc. The form of this elastomer may be a bale or sheet cut or crushed into appropriate sizes, a latex obtained by emulsion polymerization, a crumb coagulated from the latex, or a polymer solution obtained by solution polymerization. Good too.

In the present invention, the mixing ratio of PVC and nitrile elastomer is 1 to 99 times the former in the mixture.

The latter 99-1% by weight, preferably the former 20-80% by weight
, the latter ranges from 80 to 20% by weight, and is determined as appropriate depending on the purpose.

The solvent for the nitrile elastomer used in the present invention ((il) is particularly limited as long as it is incompatible with water, is a poor solvent for Pvq, and dissolves or swells the nitrile elastomer, such as benzene. ,
Toluene, cyclohexane, octyl alcohol 1. Tesyl alcohol, [vinyl chloride, vinylidene chloride, 1.2
-') Chlorethylene and the like. Of course, it is also possible to use two or more of these in combination. Among these, vinyl chloride has a low boiling point, so it does not remain in the polymer ((,
Moreover, it is extremely preferable because it is easy to collect, inexpensive, and easy to use. The amount of solvent used is 30 to 1000 parts by weight per 100 parts by weight of the nitrile elastomer.

The method of mixing the polymers in the present invention is not particularly limited, and examples include a method of mixing PVA, a nitrile elastomer, and a solvent in the presence of an aqueous medium, a method of mixing a nitrile elastomer with a solvent bath solution in advance, and then mixing it with PVC and water. The amount of water used in the present invention is usually 930 parts by weight or more, preferably 100 parts by weight, per 100 parts by weight of the total of PVC and nitrile elastomer. If the amount is less than 30 parts by weight, PVO will stick to the nitrile elastomer dissolved in the solvent and form a block, making it impossible to obtain the desired granular composite polymer. Note that the upper limit of the amount of water is not particularly limited; The amount of polymer is small (so efficiency is poor).

The aqueous medium in the present invention can contain a dispersant or emulsifier of 0 to 10 parts by weight, preferably 1 to 5 parts by weight (LOO) per 100 parts by weight of the total of PVC and nitrile elastomer.Amount of nitrile elastomer used It is preferable to coexist with a dispersant or emulsifier when there is a relatively large amount of PVC slurry or latex containing a dispersant or emulsifier after polymerization, so it may be convenient to use them as they are. .

Dispersants that may be used in the present invention include:
For example, partially saponified polyvinyl acetate, cellulose derivatives such as alkylcellulose, polyvinylpyrrolidone 1
．． Polymer electrolytes such as polyacrylic acid and polyacrylates, synthetic water-bath polymeric substances such as maleic anhydride-vinyl acetate copolymers, and natural polymeric substances such as starch, gelatin, and gum tragacanth, or one or more of them. A mixture of the following may be mentioned. Emulsifiers include partial esters of polyhydric alcohols such as fulvitan monolaurate, sorbitan triolate, and glyceryl monostearate, ethers such as polyoxyethylene nonylphenyl ether, and polypropylene glycol-polyethylene glycol block copolymers. , nonionic surfactants such as higher alcohols, sodium nistearate, higher fatty acid salts such as potassium oleate, sodium alkyl sulfates such as sodium lauryl sulfate, and alkylaryl sulfonic acids such as sodium dodecylbenzenesulfonate. Examples include anionic surfactants such as soda and sodium alkylconolate.

In the present invention, an autoclave equipped with a stirrer is used as a container for mixing PVC, nitrile elastomer, and the latter solvent. The mixing temperature varies depending on the type and amount of the two types combined, but is usually between room temperature and 80°C. In addition, there is no need to particularly limit the stirring conditions (the mixture is fluid,
All you have to do is select conditions that will disperse the information. The mixing time is not particularly limited, but is usually 30 minutes to 3 hours. If necessary, usual legumes, stabilizers, ultraviolet absorbers, antioxidants, vulcanizing agents, lubricants, pigments, fillers, reinforcing agents, etc. can be added during this mixing. Acids, alkalis, salts, coagulants, etc. can be added to obtain sized powders.

(Effects of the Invention) In this way, the present invention allows P.O.
A composite polymer in which VC and highly unsaturated nitrile elastomer are uniformly dispersed and has excellent processability, strength properties, high temperature creep properties, and flexibility can be obtained in granular form.

(Example) Next, the present invention will be described with reference to Examples, in which the number of parts shown in the Examples is based on weight (0). In addition, physical property tests of samples in Examples and Comparative Examples were conducted as follows.

100 parts of composite polymer, BIL-Z! l-based stabilizer (Mark RUP-14t manufactured by Adeka Argus, 5 parts, M
Ark AO-186t (0 parts) and 3 parts of epoxidized soybean oil were added, and this was roll-kneaded at 160°C for 5 minutes to prepare a sheet, and this sheet was heated at 170°C and a pressure of 50 k.
g/lx” for 5 minutes to determine the hardness, compression set (
70℃ x 22 hours compression), tear strength or higher J Engineering EIK-
6301), tensile properties (J Engineering 5K-6723), and number of unfused particles.

Example 1 In a stainless steel autoclave equipped with a stirrer, 200 parts of water, 15 parts of hydroxyclovir methylcellulose, 50 parts of vinyl chloride polymer with a degree of polymerization of 1000 and an average particle size of 100 μm were placed.
parts, iodine value 80, acrylonitrile content 3396,
50 parts of NBR pellets with a Mooney viscosity (ML1+4100°C) of 101 and 50 parts of vinyl chloride were added, and after stirring at 60°C for 2 hours, the vinyl chloride was recovered and dehydrated and dried to obtain a granular composite polymer. Ta.

Comparative Example 1 50 parts of the same cyclized vinyl polymer used in Example 1 and NB
A sheet-like composite polymer was obtained by mixing with 50 parts of R pellets using a roll.

Comparative Example 2 A granular composite polymer was obtained by conducting the same experiment as in Example 1, except that NBR (NBR without hydrogenation treatment) having an iodine value of 260, an acrylonitrile content of 33, and a Mooney viscosity of 78 was used.

Comparative Example 5 50 parts of the same vinyl chloride polymer used in Example 1 and 50 parts of the same NBR pellet as used in Comparative Example 2 were mixed with a roll to obtain a sheet-like composite polymer.

Example 2 An experiment similar to that in Example 1 was conducted in which the iodine value of NBR was 50 and the Mooney viscosity was 133, and a granular composite polymer was obtained.

Comparative Example 4 50 parts of the same vinyl chloride polymer used in Example 2 and NB
A sheet-like composite polymer was obtained by mixing with 50 parts of R pellets using a roll.

Example 3 The same experiment as in Example 1 was conducted, except that the average particle size of the vinyl chloride polymer was 40 μm, the iodine value of NBR was 30, the acrylonitrile content was 41%, and the Mooney viscosity was 107. A polymer was obtained.

Comparative Example 5 50 parts of the same vinyl chloride polymer used in Example 3 and N
A sheet-like composite polymer was obtained by mixing 50 parts of BR with a roll.

Example 4 A granular composite polymer was obtained by conducting the same experiment as in Example 1 except that 12-dichloroethylene was used as the vinyl chloride solvent.

The physical property test results of the composite polymers prepared on each side above are summarized in the table.

From the table, it can be seen that the composite polymers of each example have better physical properties than those of the comparative example. In particular, the effect of reducing the number of unmelted particles compared to the roll mixing method (comparison between Example 1 and Comparative Example 1) is the same as the effect of reducing the number of unmelted particles when comparing the compositions with iodine numbers of 260 ONBR and PVO. It can be seen that this is much more remarkable than (comparison between Comparative Examples 2 and 3).

Claims (1)

[Claims] Particulate vinyl chloride polymer (A), nitrile elastomer (B) with an iodine value of 120 or less, and incompatible with water,
And after mixing the solvent (C) of (B) which is a poor solvent of (A) in an aqueous medium, removing (C) and dehydrating and drying, it is possible to separate from (A) and (B). A method for producing a composite polymer, characterized by producing a granular composite polymer.