JPH0543748B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a vinyl chloride resin composition, and more particularly to a weather resistant and impact resistant vinyl chloride resin composition that has excellent processability and less deterioration of physical properties. (Prior Art) Vinyl chloride resin has excellent physical and mechanical properties and has many uses such as hard, semi-hard, and soft. However, when a vinyl chloride homopolymer is used for hard materials, it has the disadvantage of poor impact resistance and weather resistance. In order to improve these drawbacks, a polymer blend of vinyl chloride homopolymer and various elastomers.A durable vinyl chloride graft copolymer obtained by graft copolymerizing vinyl chloride to ethylene-vinyl acetate copolymer was developed. Impact composition (Special Publication No. 42-18819)
The surface of a composition made of a vinyl chloride graft copolymer (Japanese Patent Publication No. 39-17067) obtained by graft copolymerizing vinyl chloride onto an alkyl acrylate polymer is coated with a copolymer of a vinyl monomer having a functional group. A vinyl chloride resin composition containing coated titanium oxide (JP-A-58-179254) and a resin composition in which a halogen-containing resin is stabilized with a lead-based stabilizer (JP-A-57-147537) have been developed. (Problems to be Solved by the Invention) However, although the polymer blend in such conventional vinyl chloride resin compositions can improve impact resistance, it is said that weather resistance and flexural modulus are reduced. It has defects. In addition, although the impact resistance of the composition of and is improved compared to the above-mentioned polymer blend of a homopolymer and an elastomer, the weather resistance and flexural modulus are still insufficient, and the processability is also poor. There is a drawback. In addition, in the composition described above, it is necessary to use a copolymer of a vinyl monomer having a functional group on the surface of titanium oxide, and titanium oxide must be coated with a copolymer of a vinyl monomer having a functional group. This method requires a coating process, which is troublesome and increases costs. Further, the composition requires the combined use of a lead-based stabilizer and an unsaturated carboxylic acid metal salt in order to improve its photostability. As mentioned above, each of the compositions known to date has advantages and disadvantages, and further improvements are desired. The purpose of the present invention is to reduce the deterioration of physical properties, improve weather resistance,
An object of the present invention is to provide a vinyl chloride resin composition that has excellent impact resistance and processability. (Means for Solving the Problems) In order to achieve the above object, the present inventors have made extensive studies and found that an alkyl acrylate and/or a homopolymer having a secondary transition temperature of -10°C or less
Alternatively, a vinyl chloride resin made by graft copolymerizing vinyl chloride to a copolymer of an alkyl methacrylate and a monomer whose homopolymer has a secondary transition temperature of 0°C or higher is used, and a specific salt-based stabilizer and a specific It has been discovered that by blending mainly crystalline titanium white, a vinyl chloride resin composition with less deterioration in physical properties, excellent weather resistance and impact resistance, and excellent processability can be obtained, and the present invention I was able to complete it. That is, the present invention provides acrylic copolymers 1 to 30
To 100 parts by weight of a vinyl chloride resin obtained by graft copolymerizing 99 to 70 parts by weight of vinyl chloride,
Excellent processability, weather resistance, and impact resistance, characterized by a combination of 0.5 to 15.0 parts by weight of dibasic lead phosphite and 0.1 to 10.0 parts by weight of titanium white whose crystal type is rutile. A vinyl resin composition is provided. The acrylic copolymer used in the present invention is
It is a copolymer mainly composed of alkyl acrylate and/or alkyl methacrylate with other monomers. As the alkyl acrylate and/or alkyl methacrylate, those having a secondary transition temperature of −10° C. or less when formed into a homopolymer are advantageous because of their excellent impact resistance. For example, ethyl acrylate,
n-propyl acrylate, iso-butyl acrylate, n-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate, n-octyl methacrylate, n-decyl methacrylate, n-dodecyl methacrylate, Examples include lauryl methacrylate. The alkyl acrylate and/or alkyl methacrylate component acts as a soft segment in both the acrylic copolymer and the graft copolymer. The amount used is 99~ in the acrylic copolymer.
The content is preferably 60% by weight; if it exceeds 99% by weight, no improvement in flexural modulus can be expected, and if it is less than 60% by weight, the impact resistance decreases, which is not preferred. In addition, other monomers to be copolymerized with alkyl acrylate and/or alkyl methacrylate act as hard segments in acrylic copolymers and graft copolymers by copolymerizing with alkyl acrylate and/or alkyl methacrylate, It is advantageous to have a copolymer with a secondary transfer temperature of 0°C or higher, such as monofunctional monomers such as olefins such as ethylene, propylene, and hexene, and aromatic compounds such as styrene, α-methylstyrene, and vinyltoluene. group vinyls, unsaturated nitriles such as acrylonitrile and methacrylonitrile, vinyl esters such as vinyl acetate and vinyl propionate, vinyl ethers such as butyl vinyl ether, octyl vinyl ether, and lauryl vinyl ether, alkyl acrylates such as methyl acrylate, and methyl methacrylate. , alkyl methacrylates such as ethyl methacrylate and propyl methacrylate, and polyfunctional monomers such as ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, (Poly)alkylene glycol acrylates or methacrylates such as 1,3-propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, diallyl phthalate, diallyl maleate,
Examples include polyallyl compounds such as diallyl fumarate and diallyl succinate, divinylbenzene, and butadiene. The amount of this monomer used is preferably 1 to 40% by weight in the acrylic copolymer; if it is less than 1% by weight, no improvement in the flexural modulus can be expected;
Exceeding this is not preferable because impact resistance decreases. Among these, methyl methacrylate, methyl acrylate, acrylonitrile, and styrene are preferably used as monofunctional monomers in order to avoid deterioration of physical properties, and they can be used alone or in combination with polyfunctional monomers. It is preferable to do so. Alkyl acrylate and/or used in the present invention
Alternatively, a copolymer of alkyl methacrylate and other monomers can be obtained by a polymerization method such as emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization using a generally known emulsifier, dispersant, catalyst, etc. Emulsion polymerization is preferably employed as the polymerization method. To obtain a copolymer by a general emulsion polymerization method, for example, pure water, an anionic emulsifier, and a water-soluble polymerization catalyst are placed in a jacketed polymerization reactor, the air inside the can is removed, and then the alkyl Acrylate and/or alkyl methacrylate and other monomers are charged, and after emulsification, the inside of the can is heated with a jacket to start the copolymerization reaction. This copolymerization reaction is an exothermic reaction, and the internal temperature is controlled by a jacket as necessary. After the reaction is completed, unreacted monomers are removed from the can to obtain an acrylic copolymer. The method of charging into the polymerization reactor is not limited. Further, if necessary, a particle size adjusting agent for the acrylic copolymer, a decomposition accelerator for the catalyst, etc. may be added to control the copolymerization reaction. Next, in the present invention, the acrylic polymer thus obtained is used as a backbone polymer for graft copolymerization. In this case, the appropriate amount of the acrylic copolymer to be used is 1 to 30 parts by weight based on 100 parts by weight of the vinyl chloride resin. If the amount of the acrylic copolymer used is less than 1 part by weight, the impact resistance will not be sufficient, and if it exceeds 30 parts by weight, the impact resistance will improve, but the flexural modulus will decrease, which is not preferable. Examples of the graft copolymerization method of the present invention include suspension polymerization, emulsion polymerization, solution polymerization, and solvent-free polymerization, but in order to carry out the present invention advantageously, suspension polymerization is preferred. is desirable. When carrying out the suspension polymerization method, the amount of water used is 1 to 5 times, preferably 1 to 3 times, the total amount of the acrylic copolymer and vinyl chloride monomer. A method for obtaining a graft copolymer resin by a general suspension polymerization method includes, for example, adding pure water, a suspension stabilizer such as hydroxypropyl methylcellulose, a radical polymerization initiator,
If necessary, a polymerization degree reducing agent is added, and the acrylic copolymer is added thereto and suspended, the air inside the can is then removed, and then vinyl chloride is charged together with other vinyl compounds as required. Thereafter, the inside of the can is heated with a jacket to dissolve the acrylic copolymer in the vinyl chloride and initiate graft copolymerization. Graft copolymerization is an exothermic reaction, and the internal temperature is controlled by the jacket as necessary. After the reaction is complete, unreacted vinyl chloride is removed from the can,
A slurry-like graft copolymer resin is obtained. The slurry is dehydrated and dried according to a conventional method to obtain a graft copolymer resin. Furthermore, the charging method to the polymerization reactor is not limited, and among the charged raw materials such as pure water, suspension stabilizer, acrylic copolymer, and vinyl chloride, the acrylic copolymer is replaced with vinyl chloride. A method of melting and charging is also adopted. In graft copolymerization, other monomers may be present in the coexistence within a range that does not reduce impact resistance, weather resistance, and other physical properties. In addition, it is advantageous to carry out the graft copolymerization by a radical polymerization method, and the radical polymerization initiators used for this purpose include lauroyl peroxide, tert-butyl peroxypivalate,
Organic peroxides such as diisopropyl peroxydicarbonate and dioctyl peroxydicarbonate; oils of azo compounds such as 2,2'-azobisisobutyronitrile and 2,2'-azobis-2,4-dimethylvaleronitrile; Examples include soluble polymerization initiators, and water-soluble polymerization initiators such as potassium persulfate and ammonium persulfate. The amount of these polymerization initiators used is 0.005 to 100 parts by weight of vinyl chloride.
The amount is preferably 1.0 part by weight. Dispersants include methylcellulose, ethylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, polyvinyl alcohol and its partially saponified products, gelatin, polyvinylpyrrolidone, organic substances such as starch, and inorganic substances such as magnesium carbonate, calcium carbonate, and calcium phosphate. used or in combination. The amount used is usually 0.01 to 1.0 parts by weight per 100 parts by weight of vinyl chloride. Furthermore, in this graft copolymerization, the chain transfer agent used in the conventional method of polymerizing vinyl monomers is 0.001 to 100 parts by weight per 100 parts by weight of vinyl chloride.
You may add 10 parts by weight. The degree of polymerization of the graft copolymer is 400-1500, preferably 700-1350. The dibasic lead phosphite used in the present invention may be used alone, but it may also be used in combination with other lead-based stabilizers, and the present invention also includes such cases. Examples of those that can be used in combination include tribasic lead sulfate, basic lead sulfite, dibasic lead stearate, basic lead stearate, lead stearate, 2-
Lead ethylhexylate, tribasic lead maleate, dibasic lead phthalate, lead salicylate, lead orthosilicate, and basic lead silicate are listed, and two or more types, mainly dibasic lead phosphite, such as tribasic They can be used in combination, such as dibasic lead sulfate and dibasic lead phosphite. The amount of dibasic lead phosphite used is 0.5 to 100 parts by weight of vinyl chloride resin.
15.0 parts by weight, preferably 2 to 10 parts by weight, 2
If the amount is less than 10 parts by weight, thermal stability will be insufficient, and if it exceeds 10 parts by weight, the effect will not change, which is economically disadvantageous, and phenomena such as blooming and foaming may occur, which is not preferable. The amount of rutile-type titanium white used is 0.1 to 10.0 parts by weight, preferably 0.5 to 5.0 parts by weight, per 100 parts by weight of the vinyl chloride resin. If the amount used is less than 0.5 parts by weight, the weather resistance will be insufficient, and if it exceeds 5.0 parts by weight, the effect will not change and it will be economically disadvantageous. The vinyl chloride resin composition of the present invention may further contain fillers, lubricants, other resins, plasticizers,
An ultraviolet absorber, an antistatic agent, an antioxidant, a conductivity imparting agent, and a flame retardant may be added. The filler is preferably calcium carbonate, with an average particle diameter of 1 μm or less, particularly preferably 0.7 μm or less, and it is advantageous to have the surface treated with a low-molecular organic substance such as a fatty acid. It is. If the particle size exceeds 1 μm, the effect of improving impact resistance is small. The amount used is 1 to 50 parts by weight, preferably 1 to 30 parts by weight, per 100 parts by weight of the vinyl chloride resin. If it is less than 1 part by weight, there is no effect of improving the impact resistance, and if it exceeds 30 parts by weight, the impact resistance will deteriorate, which is not preferable. Examples of lubricants include hydrocarbon lubricants such as natural paraffin, liquid paraffin, and polyethylene wax;
Examples include fatty acid lubricants such as stearic acid, fatty acid amide lubricants such as stearamide, ester lubricants such as ethylene glycol monostearate, higher alcohol lubricants such as stearyl alcohol, and metal soap lubricants such as calcium laurate. The effects of lubricants include adjusting the friction between the wall of the processing machine and the plastic material (external lubricity), adjusting the gelation of plastic (internal lubricity), increasing the stabilizing effect of stabilizers, and adjusting processability. In order to achieve these effects, it is advantageous to combine two or more types of materials, one having external lubricity and one having internal lubricity. The amount of lubricant used is 0.5 to 5.0 parts by weight, preferably 0.5 to 3.0 parts by weight, per 100 parts by weight of the vinyl chloride resin.If it is less than 0.5 parts by weight, a large amount of frictional heat will be generated due to insufficient internal and external lubricity. ,
It has already gelled in the compression zone, causing an increase in viscosity and temperature, causing resin decomposition and discoloration. Moreover, if it exceeds 3.0 parts by weight, the slipperiness is too strong, resulting in insufficient kneading and insufficient gelation, which is not preferable. Other resins that can be added include copolymers such as ethylene/vinyl acetate, methyl acrylate/butyl acrylate, methyl methacrylate/ethyl acrylate, methyl acrylate/butyl methacrylate, ethylene/vinyl acetate/vinyl chloride ternary copolymers, ethylene/vinyl acetate/ carbon monoxide ternary copolymer, chlorinated polyethylene,
Ternary copolymers of acrylonitrile/butadiene/styrene, methyl methacrylate/butane diene/styrene, methyl methacrylate/butyl acrylate/ethyl acrylate, methyl methacrylate/ethyl acrylate/acrylonitrile, methyl methacrylate/styrene/butyl acrylate, methyl methacrylate/butyl Examples include methacrylate/ethyl acrylate/ethyl methacrylate quaternary copolymers, and any resin that is compatible with PVC and does not impair the physical properties of the composition of the present invention may be added. Further, as the plasticizer, phthalic acid ester, trimellitic acid ester, adipic acid ester, phosphate plasticizer, epoxy plasticizer, and polyester plasticizer are used. As ultraviolet absorbers, benzophenones such as 2,4-dihydroxybenzophenone, 2-(2'-
Benzotriazole-based UV absorbers such as hydroxy-5-methylphenylbenzotriazole, and salicylic acid ester-based UV absorbers such as phenyl salicylate are used. As antistatic agents, anionic surfactants,
Cationic surfactants, nonionic surfactants, etc. are used. Examples of antioxidants include bisphenols such as 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol), monophenols such as 2,6-di-tert-butylphenol,
A hydroquinone antioxidant such as 2,5-ditertiarybutylhydroquinone is used. Carbon black, silver powder, and copper powder are used as the conductivity imparting agent. Examples of flame retardants include known halides such as chlorinated paraffin, chlorinated polyethylene, perchloropentacyclodecane, hexabromobenzene, decabromodiphenyl ether, and tetrabromobisphenol A, antimony trioxide, antimonates, Inorganic compounds such as barium metaborate, zinc borate, and aluminum hydroxide are used. The vinyl chloride resin composition of the present invention is mixed with the above-mentioned compounding agents according to the purpose, and a Henschel mixer is used.
Mix uniformly by a known method using a rib blender or the like to obtain a spider. When the powder is actually used, any of a single-screw extruder, a twin-screw extruder, and a multi-screw extruder can be employed. The composition of the present invention has excellent processability, so high-speed extrusion molding is possible in the form of powder, but it can also be formed into pellets after being pelletized using a roll, single-screw extruder, twin-screw extruder, or multi-screw extruder. A method of doing so is also adopted. (Effects of the Invention) The vinyl chloride resin composition of the present invention is suitable for hard applications, has excellent processability, has little deterioration in physical properties, and is excellent in weather resistance and impact resistance. Therefore, it is suitably used for building materials such as window frame decking materials. (Example) The present invention will be explained in detail below using Examples. Note that the parts shown in the examples are parts by weight. Examples 1 and 2 and Comparative Examples 2 and 4 to 6 2700 kg of deionized water and partially saponified polyvinyl alcohol were placed in a polymerization machine with an internal volume of 7 m ³ equipped with a stirring blade.
2.05Kg, methylcellulose 2.05Kg, 2,2'-azobisisobutyronitrile 0.075Kg and 2,2'-azobis-2,4-dimethylvaleronitrile 0.24Kg
After charging 600 kg of acrylic copolymer latex with the composition shown in Table 1 and removing the air inside, 1410 kg of vinyl chloride was charged, and after melting at 35°C for 1 hour, it was heated to 57°C.
10 hours after the start of polymerization, the internal pressure of the polymerization machine decreased to 6.5Kg/ ^cm2 , so the unreacted monomers were collected and the slurry was dehydrated and dried.1275
Kg of white powder resin was obtained. The polymerization degree of this resin was 1030, and the content of components other than vinyl chloride was 7.0%. Next, each component was mixed with the above graft copolymer according to the formulation shown in Table 1 to prepare a powder. Mixing was carried out by charging the resin and compounding agents into a No. 7 Henschel mixer, raising the temperature to 120°C, cooling to below 40°C, and discharging. This powder was kneaded with a roll at 180°C for 10 minutes, and then press-molded at 180°C to produce a 3 mm thick sheet. Congo red thermal stability, Charpy impact strength, flexural modulus, and weather resistance were measured. The results are shown in Table 1. Examples 3 and 4 Polymerization was carried out in the same manner as in Example 1, except that 675 kg of acrylic copolymer latex having the composition shown in Table 1 was used and the amount of vinyl chloride was changed to 1350 kg.
1225Kg of white powder resin was obtained. The degree of polymerization of this resin is 1050, and the content of components other than vinyl chloride is
It was 11.6%. Using this resin, a press sheet was prepared in the same manner as in Example 1 using the formulation shown in Table 1, and its physical properties were measured. The results are shown in Table 1. Comparative Example 1 2700 kg of deionized water and partially saponified polyvinyl alcohol were placed in a polymerization machine with an internal volume of 7 m ³ equipped with a stirring blade.
2.05 kg of methyl cellulose, 90 kg of ethylene-vinyl acetate copolymer (trademark Levaprene 450P, manufactured by Bayer AG) were charged, and after removing the air inside, 1410 kg of vinyl chloride was charged and heated at 65℃ for 30 minutes. After dissolution for an hour, 2,2'-azobisisobutyronitrile
0.375Kg was dissolved in acetone, loaded, and polymerization was continued under the same conditions. 10 hours after starting the polymerization, the internal pressure of the polymerization machine decreased to 8.5Kg/ ^cm2 , so the unreacted monomer was collected, and the slurry was dehydrated and dried. When I did that
1250Kg of white powder resin was obtained. The degree of polymerization of this resin is 900, and the content of components other than vinyl chloride is
It was 7.0%. Using the above graft copolymer, a press sheet was prepared in the same manner as in Example 1 using the formulation shown in Table 1, and its physical properties were measured. The results are shown in Table 1. Comparative Example 3 In Example 1, the charging of 600 kg of acrylic copolymer latex was stopped, and 1410 kg of vinyl chloride was charged.
Polymerization was carried out in the same manner as in Example 1, except that the weight was changed to 1500 kg and the dissolution time was stopped for 1 hour at 35°C.
Kg of white powder resin was obtained. The degree of polymerization of this resin was 1050. Example 1: 90% by weight of this resin and 10% by weight of the acrylic rubber shown in Table 1 were mixed with the formulation shown in Table 1.
A press sheet was prepared in the same manner as above, and its physical properties were measured. The results are shown in Table 1. In the above Examples and Comparative Examples, Congo Red Heat Stability was measured in accordance with JIS K-6723 (oil bath temperature 180°C). Shalpey impact strength was measured according to JIS K-6745. The bending modulus is
Measured according to JIS K-6740. Weather resistance was evaluated by irradiating for 200 hours with a carbon arc sunshine weather meter (spray 12/60 minutes, black panel 63°C) and comparing discoloration. From the results shown in Table 1, it can be seen that the composition of the present invention has no decrease in thermal stability, impact resistance, or flexural modulus, and is also excellent in weather resistance.

【table】

[Table] Test Examples 1 and 2 The powders obtained in Examples 1 and 3 were subjected to an extrusion test using a φ30 mm bidirectional twin-screw extruder (manufactured by Plastic Engineering Research Institute). The conditions and results are shown in Table 2. Test Examples 3 to 5 The powders obtained in Comparative Example 1, Comparative Example 2, and Comparative Example 3 were subjected to an extrusion test in the same manner as in Test 1. The conditions and results are shown in Table 2. Table 2 shows that the composition of the present invention has excellent processability.

[Table] (Note) 〓〃〓 in the table means 〓same as above〓.

Claims (1)

[Claims] 1 For 1 to 30 parts by weight of acrylic copolymer,
To 100 parts by weight of a vinyl chloride resin obtained by graft copolymerizing 99 to 70 parts by weight of vinyl chloride, 0.5 to 15.0 parts by weight of dibasic lead phosphite and 0.1 to 10.0 parts by weight of titanium white whose crystal type is rutile. A weather-resistant and impact-resistant vinyl chloride resin composition with excellent processability.