JPS6219464B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing thermoplastic polyamide or polyester resin compositions with improved properties. Thermoplastic polyamide resins (hereinafter referred to as polyamides) such as polycaproamide and polyhexamethylene adipamide, and thermoplastic polyester resins (hereinafter referred to as polyesters) such as polyethylene terephthalate and polybutylene terephthalate, both have excellent mechanical properties. properties, electrical properties,
Due to its chemical resistance and processability, fibers,
It is used in many fields such as films and plastic products. However, while polyamide and polyester have these excellent properties,
Both materials have the disadvantage of low impact resistance when notched, so they are not necessarily satisfactory materials for use in a wider range of applications. Traditionally, glass fiber,
A method of adding fibrous reinforcing agents such as asbestos fibers and carbon fibers is known, but when such fibrous reinforcing agents are added to polyamides and polyesters, the effect of improving impact resistance is still insufficient. Moreover, there is a problem in that warpage occurs in the molded product. In addition, in order to improve the impact resistance of polyamide and polyester, a technology has been proposed in which various polymers are blended with polyamide and polyester.
(A) A method of mixing a tertiary graft copolymer consisting of butadiene rubber, styrenes and acrylonitriles (Japanese Patent Publication No. 38-23476), (B) A method of mixing a copolymer of olefin and vinyl acetate ( (Special Publication No. 44-29262), (C) Olefin and No. 3
A method of mixing copolymers consisting of acrylic esters and/or methacrylic esters of alcohols (Japanese Patent Publication No. 46-26791) and (D) unsaturated rubber-like polymers such as butadiene rubber or acrylic rubber. A method of mixing a multiphase polymer obtained by graft copolymerizing a monomer mixture containing a monomer having a reactive functional group with a polyamide such as a carboxylic acid (Japanese Unexamined Patent Publication No. 47-6284), etc. can be mentioned. Regarding polyester, (E) a method of mixing a rubber-modified methyl methacrylate-styrene copolymer (Japanese Patent Publication No. 51-25261), and (F) a method of blending an acrylate-based rubber-modified alkyl methacrylate or alkyl acrylate resin. (Japanese Unexamined Patent Publication No. 1982-82749) (G) A method of blending a lantum copolymer having a tensile modulus of 10% or less of the tensile modulus of the polyester resin serving as the matrix resin (Japanese Unexamined Patent Publication No. 51-14452) , (Unexamined Japanese Patent Publication No. 1973-
143061) have been proposed. However, although the polyamide composition and polyester composition obtained by the above method have slightly improved impact resistance, the impact resistance when notched is still unsatisfactory. Also above (D)
The multilayer polymer obtained by this method is a rubber-like polymer,
Since monomers containing α/β-unsaturated carboxylic acids are subjected to emulsion graft polymerization, it is difficult to recover the multilayer polymer from the latex after polymerization using known electrolytes. Since the latex must be recovered by a spray drying method or the latex must be directly mixed with the polyamide, the resulting composition contains a large amount of impurities, and its impact resistance improvement effect is also unsatisfactory. The present inventors conducted extensive research to obtain a new resin composition made by improving the impact resistance of polyamide and polyester, and found that a saponified acrylic rubber-like polymer or An acrylic rubber whose lower layer polymer is an acrylic rubber-like polymer and whose upper layer polymer is a vinyl unsaturated monomer containing as an essential component an unsaturated carboxylic acid ester monomer having an active double bond. The inventors have discovered that a saponified acrylic rubber grafted vinyl polymer obtained by saponifying a grafted vinyl polymer has a remarkable effect of improving the impact resistance of polyamides and polyesters, and have arrived at the present invention. However, when the saponified acrylic rubber-like polymer or saponified acrylic rubber-modified vinyl polymer is blended into a polyamide or polyester composition containing a fibrous reinforcing agent, shrinkage of the molded article made from the composition may be reduced. It has been found that the anisotropy is improved and the occurrence of warpage is significantly suppressed. That is, the present invention provides A. at least one selected from thermoplastic polyamide resins and thermoplastic polyester resins; B. (a) a saponified acrylic rubber-like polymer obtained by saponifying an acrylic rubber-like polymer; (b) 20 parts by weight or more of an acrylic rubber-like polymer as the lower layer polymer, 5 to 100% by weight of an unsaturated carboxylic acid ester monomer having an active double bond, an aromatic vinyl monomer, and cyanide. One or more vinyl monomers selected from vinyl monomers95~
At least one type selected from saponified acrylic rubber grafted vinyl polymers obtained by saponifying acrylic rubber grafted vinyl polymers in which the upper layer polymer is 80 parts by weight or less of a hard polymer consisting of 0% by weight. and C. Thermoplastic material containing at least one fibrous reinforcing agent in a ratio of 0 to 200 parts by weight of C to a total of 100 parts by weight of 50 to 95 parts by weight of A and 50 to 5 parts by weight of B. A method for producing a resin composition is provided. The most distinctive feature of the present invention is to avoid direct polymerization of monomers having carboxyl groups, such as acrylic acid, into the polymer blended into polyamide or polyester, and to prevent active double bonds from being directly polymerized. After polymerizing an unsaturated carboxylic acid ester monomer, the polymer is saponified to contain carboxyl groups in the acrylic rubber-like polymer and the acrylic rubber-grafted vinyl polymer, As a result, the following excellent effects can be obtained. (1) Polymerization is easy because no ionically dissociable monomers such as unsaturated carboxylic acids are used, and the polymer can be easily recovered from the polymerization system. (2) The composition of the present invention comprising the obtained saponified polymer and polyamide or polyester has extremely high impact strength, and also extremely well prevents warping when a fibrous reinforcing agent is blended. (3) Industrially inexpensive unsaturated carboxylic acid ester monomers can be used. The polyamides that can be used in the present invention are not particularly limited, and include ethylenediamine, hexamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4- and 2,4,4-trimethylhexamethylenediamine, 1,3 and 1,4-bis(aminomethyl)cyclohexane,
Bis(p-aminocyclohexyl)methane, m-
Aliphatic, alicyclic, and aromatic diamines such as xylylene diamine and p-xylylene diamine, and aliphatic, alicyclic, and aromatic diamines such as adipic acid, suberic acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid, and isophthalic acid. Polyamides derived from dicarboxylic acids of the group A, polyamides obtained by ring-opening polymerization of lactams such as ε-caprolactam and ω-dodecalactam, 6-aminocaproic acid, 11
-aminoundecanoic acid, 12-aminododecanoic acid,
Polyamides derived from polyamides, copolyamides and mixed polyamides of these polyamides are industrially inexpensive and manufactured in large quantities, so polycaproamide (nylon 6), polydodecaamide (nylon 12), polyhexane Methylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610) and copolymers thereof,
For example, nylon 6/66 (〃/〃 symbol means copolymer), nylon 6/610, nylon 6/12,
Nylon 66/12, nylon 6/66/610/12 and mixtures thereof are useful. Furthermore, there is no particular restriction on the degree of polymerization of the polyamide used here, and usually the relative viscosity (1 g of polymer is 98%
Dissolved in 100ml of sulfuric acid and measured at 25℃ (same below) is 1.8
Although any polyamide within the range of ~6.0 can be selected, high viscosity polyamides are generally desirable to obtain high impact resistance. There are no restrictions on the molecular structure of polyamide, and linear polyamides and branched polyamides are prepared by using branching agents that have three or more functional groups capable of forming polyamides in the raw materials, such as bis(ω-aminohexyl)amine, diethyltriamine, trimesic acid, Polymerize by adding a small amount of bislactam, etc. As the polymerization method, melt polymerization, interfacial polymerization, solution polymerization, bulk polymerization, solid phase polymerization, and a combination of these methods are used, and melt polymerization is generally most suitable. Further, particularly when the polyamide raw material is a lactam, the polymer may be obtained by anionic polymerization. The polyester that can be used in the present invention is not particularly limited, but it is one obtained from a polycondensate of dicarboxylic acid or a derivative such as an alkyl ester of dicarboxylic acid and a diol, and among the constituent components of the polyester, dicarboxylic acid Of the moiety constituted by It is something that The moiety composed of glycol is introduced by ethanediol, propanediol, butanediol, pentanediol, and hexanediol, and may be composed of two or more of these. There may also be a portion introduced by oxybenzoic acid or bisphenol A, and mixed polyesters containing one or more of these polyesters are also included within the scope of the present invention. Such polyesters include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, copolymers and mixed polymers thereof, and terephthalic acid of these polymers.
Contains up to 30 mol% of isophthalic acid. Next, the saponified product of the acrylic rubber-like polymer or the acrylic rubber-grafted vinyl polymer to be blended with the above-mentioned polyamide or polyester will be explained. First, the acrylic rubber-like polymers used in the present invention are ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, and acrylic acid.
A polymer with a glass transition temperature of 0°C or lower, which is mainly composed of an acrylic ester having an alkyl group of 2 to 12 carbon atoms, such as 2-ethylhexyl, octyl acrylate, and lauryl acrylate. In the following, copolymers of acrylic acid ester monomers and other copolymerizable monomers that do not contain carboxyl groups are also included if they exhibit rubber elasticity at room temperature. The lower layer polymer of the acrylic rubber-grafted vinyl polymer is the above-mentioned acrylic rubber-like polymer containing polyfunctional monomers such as divinylbenzene, monoallyl maleate, and triallyl cyanurate. is preferred. Methods for producing the lower layer polymer of acrylic rubber-like polymers and acrylic rubber-grafted vinyl polymers include emulsion polymerization,
Suspension polymerization, solution polymerization, etc. are possible, and there are no particular technical restrictions, but for the lower layer polymer, 1% by weight or more of an unsaturated carboxylic acid ester monomer having an active double bond is added in the next step. When the monomer contained as an essential component is emulsion polymerized to form the upper layer polymer, the lower layer polymer needs to be in an emulsified state. Further, if the glass transition temperature of the lower layer polymer of the acrylic rubber-like polymer and the acrylic rubber-grafted vinyl polymer is not lower than 0°C, the rubbery properties will be insufficient, which is not preferable. Next, the unsaturated carboxylic acid ester monomers having active double bonds that are included as essential components in the monomers forming the upper layer polymer of the acrylic rubber grafted vinyl polymer are methyl methacrylate and butyl methacrylate. , methacrylic acid ester monomers such as amyl methacrylate, cyclohexyl methacrylate, and derivatives thereof, and acrylic acid, maleic acid, fumaric acid, which have similar ester groups,
It is an ester of unsaturated carboxylic acid having an active double bond in the molecule, such as itaconic acid and cinnamic acid, and its derivatives. Vinyl monomers to be copolymerized with unsaturated carboxylic acid esters having active double bonds are aromatic vinyl monomers represented by styrene, cyanide vinyl monomers represented by acrylonitrile, etc., if necessary. It is a vinyl monomer consisting of monomers. If the vinyl monomer copolymerized into the acrylic rubbery polymer and the upper layer polymer of the acrylic rubbery polymer has a functional group that is ionizable in water, such as a carboxyl group, due to its ionic nature. This is undesirable because coagulation is likely to occur during emulsion graft polymerization, and recovery of the obtained polymer is extremely difficult by a conventional coagulation method using an electrolyte. The amount of the lower layer polymer in the acrylic rubber grafted vinyl polymer is preferably 20 parts by weight or more, preferably 40 parts by weight or more. This is not preferable because the proportion of coalescence becomes relatively small and the impact resistance of the finally obtained mixed composition with polyamide and polyester decreases, so that the object of the present invention is not achieved. The monomer composition of the upper layer polymer is 5 to 100% by weight of an unsaturated carboxylic acid ester monomer having an active double bond based on the upper layer polymer. An acrylic rubber-like polymer is used as the lower layer polymer, and 100% by weight of unsaturated carboxylic acid ester monomers containing active double bonds and other copolymerizable vinyl monomers containing no carboxyl groups 99 As a method for producing a multilayer polymer in which the upper layer polymer is a monomer mixed with 0% to 0% by weight, a conventional method for producing rubber-modified impact-resistant resins can be used. For example, when polymerizing monomers that will become the upper layer polymer in the presence of an acrylic rubbery polymer, potassium persulfate, ammonium persulfate, benzoyl peroxide, cumene hydroperoxide, t
- Peroxide initiators such as butyl perbenzoate and t-butyl peracetate, sodium salts and potassium salts of higher fatty acids such as lauric acid and oleic acid, alkali salts of alkylbenzene sulfonic acids, disproportionated rosin salts, etc. By coexisting a selected anionic surfactant or nonionic surfactant and a polymerization aid, a polymer can be easily produced by emulsion polymerization. Alternatively, it may be obtained by mixing an upper layer polymer and a lower layer polymer obtained by separate polymerization. Next, saponification as referred to in the present invention is usually achieved by treating the acrylic rubber-like polymer and the acrylic rubber-grafted vinyl polymer in a basic or acidic aqueous solution. The basic aqueous solution mentioned here refers to the first
Examples include aqueous solutions of hydroxides, carbonates, carboxylates, and alkoxy compounds of Group 2 alkali metals and alkaline earth metals. Further, the acidic aqueous solution is an aqueous solution of sulfuric acid, hydrochloric acid, etc., and it is sufficient if the so-called aqueous solution exhibits basicity or acidity. The forms of the acrylic rubber-like polymer and the acrylic rubber-grafted vinyl polymer to be subjected to the saponification treatment include suspension, which is the final state of polymerization in which they are obtained;
It may be in an emulsified or solution state, or it may be in the form of a powder obtained by coagulating it in advance with an electrolyte, washing, and dehydration, or it may be in a solution obtained by dissolving it in a solvent. The general conditions for saponification of the acrylic rubber-like polymer and the acrylic rubber-grafted vinyl polymer used in the present invention are as follows, taking into account the economic efficiency of the saponification process.

[Adjustment and saponification treatment of acrylic rubber-like polymer]

200 parts of water, 3 parts of sodium lauryl sulfate and 0.4 parts of potassium persulfate are placed in a reactor equipped with a thermometer, stirrer, dropping funnel, gas inlet tube and reflux condenser.
The inside of the reactor was purged with nitrogen, and while the temperature was controlled at 70°C, a monomer mixture of 92 parts of butyl acrylate (BA), 8 parts of acrylonitrile (AN), and 0.2 parts of divinylbenzene (DVB) was stirred. The solution was added dropwise over 1 hour. The reaction continued for an additional 3 hours and was completed. The temperature of this polymer latex was raised to 80°C, and a solution of 5 parts of sodium hydroxide and 50 parts of water was added to this latex and stirred for 8 hours for saponification. This latex was neutralized with sulfuric acid, coagulated with 5 parts of calcium chloride (per 100 parts of polymer), filtered and dried to obtain a saponified copolymer (BA-AN-DVB). [Mixing of polyamide, polyester, and saponified polymer and evaluation of composition] Polycaproamide (nylon 6) obtained by melt polymerizing ε-caprolactam and having a phase viscosity of η _r 3.40.
and the saponified copolymer (BA-AN-DVB) obtained by the above method were mixed in a ratio of 80/20, melt-kneaded in an extruder with a 40 mm diameter bed, and pelletized. After vacuum drying the pellets, the molded products obtained by injection molding were examined for mechanical properties, mainly impact resistance, and the results are shown in Table 1. In addition, polybutylene terephthalate (PBT) with a relative viscosity of η _r 1.70 obtained by condensation polymerization of terephthalic acid dimethyl ester and tetramethylene glycol and the saponified product of the above polymer were used.
The physical properties of a composition mixed in a ratio of 80/20 were measured in exactly the same manner, and the results are shown in Table 1. It is clear that both compositions have very good impact resistance. Examples 2 and 3 Polymerization and saponification were carried out in the same manner as in Example 1, except that the composition of the monomers to be polymerized was changed as shown below. After kneading, the physical properties of the composition were measured. The results are shown in Table 1.

[Table] Comparative Example 1 The polymer latex obtained in Example 1 was coagulated and recovered without being saponified, and the polymer was kneaded with polyamide and polyester in exactly the same manner, and the physical properties of the composition were measured. The results are shown in Table 1. Comparative Example 2 The same procedure as in Example 1 was repeated except that the composition of the monomers to be polymerized was changed to 75 parts of butyl acrylate, 10 parts of acrylonitrile, 15 parts of acrylic acid, and 0.2 parts of divinylbenzene, and then coagulation was performed with calcium chloride. However, the polymer did not coagulate even after adding 20 parts per 100 parts of the polymer, so the polymer was recovered by a spray drying method. Similarly, the composition was melt-kneaded with polyamide and polyester, and the physical properties of the composition were measured. Results first
Shown in the table.

【table】

[Table] Example 4 A polymer was obtained using the same recipe as in Example 1 except that the monomer composition was changed to 24 parts of styrene, 4 parts of acrylonitrile, and 72 parts of methyl methacrylate, and 40 parts of the polymer was obtained. (solid content ratio) and Example 1
After latex blending 60 parts (solid content ratio) of the acrylic rubber-like polymer obtained, an aqueous solution of 10 parts of potassium hydroxide and 100 parts of water was added, and the mixture was saponified at 90°C for 10 hours. A saponified product of an acrylic rubber-grafted vinyl polymer was obtained. Next, the saponified polymer was collected in the same manner as in Example 1, and then kneaded with polyamide and polyester, and the physical properties of the composition were measured. This result is the second
Shown in the table.

[Adjustment of lower layer polymer of acrylic rubber grafted vinyl polymer]

Into the reaction vessel used in Example 1 were added 200 parts of water, 1.5 parts of sodium lauryl sulfate, and potassium persulfate.
The temperature was adjusted to 70°C under a nitrogen atmosphere, and 1.5 parts of a monomer mixture consisting of 46 parts of butyl acrylate, 46 parts of 2-ethylhexyl acrylate, 4 parts of acrylonitrile, and 4 parts of monoallyl maleate was charged.
It was dripped over a period of time. After completion of the dropwise addition, polymerization was continued for 3 hours at 70°C to obtain a lower layer polymer of acrylic rubber grafted vinyl polymer. [Preparation of acrylic rubber-grafted vinyl polymer, saponification treatment, mixing of polyamide and polyester, and evaluation of composition] Into the reaction vessel used in Example 1, 50 parts (solid content) of the lower layer polymer latex obtained above, 0.4 parts of sodium formaldehyde sulfoxylate, 0.5 parts of sodium ethylenediaminetetraacetate, and 180 parts of water (including water in the latex) were charged, and the temperature was adjusted to 65°C. While stirring, a mixture of 8 parts of styrene, 2 parts of acrylonitrile, 40 parts of methyl methacrylate and 0.3 parts of n-dodecylmercaptan was added dropwise over 4 hours. On the other hand, a separately prepared mixture of 0.3 parts of cumene hydroperoxide, 2 parts of sodium dodecylbenzenesulfonate, and 20 parts of water was added dropwise over 5 hours in the same manner as when the monomer mixture was started.
The reaction was stopped after 6 hours. A solution of 14 parts of sodium hydroxide and 50 parts of water was added to this graft polymer latex, the temperature was adjusted to 130°C, and the mixture was stirred for 4 hours for saponification. After cooling to room temperature, the saponified polymer was collected in the same manner as in Example 1, kneaded with polyamide and polyester, and its physical properties were measured. The results are shown in Table 3. Comparative Example 3 The acrylic rubber-grafted vinyl polymer obtained in Example 5 was coagulated without saponification, washed, dehydrated, and dried, and then melt-kneaded with polyamide and polyester,
The physical properties of the composition were measured. The results are shown in Table 3.
When an acrylic rubber-grafted vinyl polymer that is not saponified is blended, the impact strength is low. Comparative Example 4 The monomer mixture polymerized as the upper layer polymer in Example 5 was mixed with 8 parts of acrylonitrile and 32 parts of styrene.
graft polymerization was carried out using the same recipe except that 10 parts of acrylic acid was used, and a graft polymer latex was obtained.
I tried to coagulate this with calcium chloride, but
Since it did not coagulate even after adding 20 parts per 100 parts of the polymer, the polymer was recovered by a spray drying method.
The composition was melt-kneaded with polyamide and polyester, and the physical properties of the composition were measured. The results are shown in Table 3.

[Table] Examples 6 and 7 20 parts of the saponified polymer obtained in Examples 1 and 5, polyhexamethylene adipamide and polyethylene terephthalate (80 parts each) were melt-kneaded in the same manner as in Example 1, and a composition was prepared. The physical properties of the material were measured. The results are shown in Table 4. Comparative Example 5 The physical properties of polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polybutylene terephthalate (PBT) and polyethylene terephthalate (PET) were measured, and the results are shown in Table 4.

【table】

[Table] Examples 8 and 9 20 parts by weight of the saponified polymer obtained in Examples 1 and 5, a total of 100 parts each of polycaproamide, polyhexamethylene adipamide, polybutylene terephthalate, and polyethylene terephthalate, and glass. After uniformly kneading 50 parts of fiber (CSX-3P-231 manufactured by Nittobo Co., Ltd.), it was melt-kneaded in a vented extruder, and the mechanical properties of the composition were determined. The board was placed on a horizontal surface, and the distance from the horizontal surface to the farthest part was measured as the amount of warpage. The results are shown in Table 5. Comparative Example 6 Table 6 shows the physical properties of a composition consisting of 100 parts each of polycaproamide, polyhexamethylene adipamide, polyethylene terephthalate and polybutylene terephthalate and 50 parts of glass fiber.

【table】

【table】

[Table] Example 10 The monomer mixture polymerized as the upper layer polymer in Example 5 was mixed with 8 parts of acrylonitrile and 32 parts of styrene.
1 part, except that it was changed to 10 parts of methyl methacrylate.
Graft polymerization was carried out using the same recipe to obtain a graft polymer latex. A solution of 5 parts of sodium hydroxide and 50 parts of water was added to this latex and stirred for 8 hours for saponification. After neutralizing this latex with sulfuric acid, calcium chloride (per 100 parts of polymer)
It was coagulated with 5 parts, filtered and dried to obtain a saponified acrylic rubber grafted vinyl copolymer. This was kneaded with polyamide and polyester in the same manner as in Example 1, and the physical properties of the composition were measured. The results are shown in Table 7.

【table】

【table】

Claims (1)

[Claims] 1 A. At least one selected from thermoplastic polyamide resin and thermoplastic polyester resin, B.
(a) A saponified acrylic rubbery polymer obtained by saponifying an acrylic rubbery polymer and (b) 20 parts by weight or more of an acrylic rubbery polymer as the lower polymer, and active double bonds are formed. 5 to 100% by weight of unsaturated carboxylic acid ester monomers and 95 to 0% by weight of one or more vinyl monomers selected from aromatic vinyl monomers and vinyl cyanide monomers. At least one selected from saponified acrylic rubber-grafted vinyl polymers obtained by saponifying acrylic rubber-grafted vinyl polymers containing 80 parts by weight or less of a hard polymer as an upper layer polymer, and
C. Add at least one fibrous reinforcing agent to 100 parts by weight of 50 to 95 parts by weight of A and 50 to 5 parts by weight of B.
1. A method for producing a thermoplastic resin composition, which is blended in a proportion of 0 to 200 parts by weight.