JPS6039093B2 - Thermoplastic polyester resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to thermoplastic polyester resin compositions having improved properties.

More specifically, the present invention relates to a gen-based rubbery polymer and a Q
・Saponified graft copolymer prepared by saponifying a graft copolymer containing an 8-unsaturated carboxylic acid ester monomer as an essential component, a thermoplastic polyester resin, and fibrous reinforcement if necessary. The main purpose of its modification is to improve the impact resistance of polyester resin, to suppress the anisotropy of shrinkage of polyester resin molded products reinforced with fibrous reinforcing agents, and to reduce warpage. The point is to suppress the amount of generation.

Thermoplastic polyester resins such as polyethylene terephthalate and polybutylene terephthalate (hereinafter abbreviated as polyester).

'' has excellent mechanical properties, electrical properties, heat resistance, chemical resistance, low moisture absorption, processability, etc., so it is used in many fields such as fibers, films, and plastic products. However, while polyester has these excellent properties, it has the disadvantage that it does not have very good impact resistance, especially when notched. Conventionally, it has been known to add inorganic fillers such as glass fibers, asbestos fibers, and talc to polyester to give it rigidity and impact resistance.
From the viewpoint of improving the mechanical properties of polyester, it is said that polyester containing a fibrous reinforcing agent such as glass fiber is most desirable.

However, when such a fibrous reinforcing agent is blended with polyester, the effect of improving impact resistance is still insufficient, and the molded product has a large anisotropy in molding shrinkage rate, resulting in undesirable warping. There are drawbacks. In addition, in order to improve the impact resistance of polyester, techniques have been proposed for blending various polymers with polyester. One of these methods is to mix a rubber-modified methyl methacrylate-styrene copolymer with wind polyester. (Tsubaki Publication No. 51-25261) 'B} Method of blending acrylate-based rubber-modified alkyl methacrylate or alkyl acrylate resin (Japanese Unexamined Patent Publication No. 491-8274) [C-acrylate-based ionic graft copolymer (Japanese Patent Publication No. 48-4843) ■ A method of blending a random copolymer having a tensile modulus of 10% or less of the tensile modulus of the polyester resin serving as the matrix resin (
Special Publication No. 51-14452, Japanese Unexamined Patent Publication No. 51-1430
Publication No. 61).

However, although the impact resistance of the polyester compositions obtained in steps 1 to 'D} above is slightly improved, the impact resistance when notched is not necessarily satisfactory. Therefore, the present inventors conducted extensive research to obtain a new resin composition that improves the impact resistance of polyester.
A polymer obtained by graft copolymerizing a Q.3 monounsaturated carboxylic acid ester monomer with a Gen-based rubber and saponifying the resulting graft copolymer has a remarkable impact resistance improvement effect on polyester. They discovered this and arrived at the present invention. That is, the present invention is directed to the A{a}-based rubbery polymer 2.
In the presence of 0 to 90 parts by weight, {b) 5 to 10% by weight of an 8-unsaturated carboxylic acid ester monomer selected from aromatic vinyl monomers and vinyl cyanide monomers; A graft copolymer obtained by emulsion graft polymerization of 80 to 1 part by weight of a monomer or a monomer polymer containing 95 to 0% by weight of one or more vinyl monomers is saponified. Gen-based rubber modified graft copolymer saponified product, B
A polyester composition prepared by blending polyester and a fibrous reinforcing agent in a ratio of 0 to 200 parts by weight of C to a total of 10 parts by weight of A5 to 5 parts by weight and 95 to 50 parts by weight of B. This is what we provide. The most distinctive feature of the present invention is that when producing a rubber-modified graft polymer in which the lower layer polymer is a gene-based rubbery polymer for blending with polyester and the upper layer polymer is a carboxyl group-containing polymer, unsaturated Instead of directly graft copolymerizing the carboxylic acid monomer, the unsaturated carboxylic acid ester monomer was emulsion graft polymerized, and then the graft copolymer was saponified. By blending the polymer into polyester, a polyester composition having significantly higher impact resistance than conventional polyester compositions was obtained.

In the present invention, the Jen-based rubber-like polymer used as the lower layer polymer of the saponified Jen-based rubber-modified graft copolymer is composed of conjugated Jen-based monomers such as butadiene, isoprene, 2,3-dimethylbutadiene, and chloroprene. a homopolymer of butadiene or butadiene and styrene, acrylonilyl, methyl methacrylate, butyl acrylate,
A copolymer such as divinylbenzene may also be used.

Emulsion polymerization, solution polymerization, etc. are possible as methods for producing these Gen-based rubbery polymers, and although there are no particular technical limitations, Q.8 monounsaturated carboxylic acid ester monomers may be added as an essential component. When carrying out emulsion graft polymerization of the monomers contained therein, it is necessary that the gene-based polymer be in an emulsified state. Furthermore, if the proportion of the diene monomer in the diene polymer is less than 5% by weight, the rubbery properties of the polymer will deteriorate, which is not preferable. Next, the Q.8 monounsaturated carboxylic acid ester monomers, which are contained in an amount of 5% by weight or more as an essential component in the monomers to be emulsion graft polymerized to the above-mentioned Gen-based rubbery polymer substrate, are methyl acrylate, acrylic ethyl acrylate, n-propyl acrylate, n-butyl acrylate, jso-butyl acrylate, t-butyl acrylate,
n-amyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, lauryl acrylate, cyclohexyl acrylate, 2-ethoxyethyl acrylate, jetylaminoethyl acrylate, glycidyl acrylate, tetrahydro acrylate Acrylic acid esters such as furfuryl, pendyl acrylate, and phenyl acrylate, and methacrylic acid esters having similar ester group moieties, maleic acid ester, fumaric acid ester, itaconic acid ester, citraconic acid ester, acomitic acid triester, and crotonic acid ester ,
These include cinnamic acid ester, methylmalonic acid ester, 2-methylglutaric acid ester, and 3-butene-1,2,3-tricarboxylic acid ester.

The aromatic vinyl monomers and vinyl cyanide monomers copolymerized with these Q-8-unsaturated carboxylic acid esters are styrene, vinyltoluene, Q-
Methylstyrene, ethylvinylbenzene, P- to rt-butylstyrene, 2,4-dimethylstyrene, 2,5-
Dimethylstyrene, o-chlorostyrene, p-chlorostyrene, 2,5-dichlorostyrene, p-phenylstyrene, p-methoxystyrene, p-benzylstyrene,
These include vinylnaphthalene, vinylpyridine, acrylonitrile, and methacrylonitrile. The proportion of the monopod to be graft-polymerized with the DEN-based rubbery polymer is 20 to 9 parts by weight, preferably 40 to 8 parts by weight of the DEN-based rubbery polymer.
80 to 1 part by weight, preferably 60 to 20 parts by weight, of the monomer to be graft-polymerized with parts by weight of. When the amount of the monomer to be graft-polymerized is 80 parts by weight or more, the proportion of the gene-based rubbery polymer in the graft copolymer becomes relatively small, and accordingly, the mixed composition with the polyester finally obtained decreases. The impact resistance of the object decreases and the original purpose cannot be achieved. On the other hand, if the amount of the monomer to be graft-polymerized is less than 1 part by weight, the resistance of the mixed composition with the polyester is likely to be due to a decrease in the compatibility between the saponified graft copolymer and the polyester. This is not preferable because it causes a decrease in impact resistance.

In addition, the composition of the monomer to be graft-polymerized to the lower layer polymer is 5 to 1 Q.6-unsaturated carboxylic acid ester monomer based on the total amount of the monomer to be graft-polymerized.
0% by weight.

5 to 10% by weight of a Q.8-unsaturated carboxylic acid ester monomer and one or more vinyl selected from aromatic vinyl monomers and vinyl cyanide monomers in a rubbery polymer. As a method for graft polymerizing a mixed monomer containing 95% and 0% by weight of the system monomer, a conventional method for producing a rubber-modified impact-resistant resin can be used.

For example, when polymerizing a vinyl single island in the presence of a gene polymer, potassium persulfate, ammonium persulfate, benzoyl peroxide, cumene hydroperoxide, t-butyl/f-penzoate, t-butyl/g-
Peroxide initiators such as acetate, sodium salts and potassium salts of higher fatty acids such as lauric acid and oleic acid,
By coexisting an anionic surfactant or a nonionic surfactant selected from alkali salts of alkylbenzene sulfonic acids, disproportionated rosinate salts, and a polymerization aid, the graft copolymer can be produced by emulsion polymerization. It can be easily manufactured. In addition, in this graft copolymerization method, not all of the monomers normally used are graft-polymerized to the gene-based polymer, and some of them generate free polymers, but when mixing with the polyester, these free polymers are There is no problem even if polymers coexist. Next, saponification as referred to in the present invention is usually achieved by treating the graft copolymer in a basic aqueous solution. The basic aqueous solution referred to here refers to hydroxides of alkali metals and alkali metals of Group 1 and Group 2 represented in the periodic table,
Examples include aqueous solutions of carbonates, carboxylates, alkoxy compounds, etc., but any so-called aqueous solution exhibiting basicity may be used. The form of the graft copolymer to be subjected to the saponification treatment is an emulsion obtained by emulsion graft polymerization of a monomer containing a Q.8-unsaturated carboxylic acid ester monomer as an essential component to a lower layer polymer of a gen-based polymer. It may be in a latex state after completion of polymerization, it may be in a powder form which has been coagulated in advance by negative electrolysis, washed, dehydrated and recovered, or it may be in a solution obtained by dissolving it in a solvent. The general conditions for saponification of the graft copolymer used in the present invention are as follows, taking into consideration the economic efficiency of the saponification treatment. In other words, it is necessary that the Q.8-unsaturated carboxylic acid ester monomer portion contained in the graft polymer be hydrolyzed by the saponification treatment, and if that purpose is achieved, general Equipment, formulations, conditions, etc. are used in the saponification treatment of ester compounds such as ethyl acetate and fats.

Even if the Jen-based rubber-modified graft copolymer is blended with polyester as it is without such saponification treatment, no significant improvement in impact resistance can be expected. The polyester that can be used in the present invention is obtained by polycondensation of dicarboxylic acid or a derivative such as an alkyl ester of dicarboxylic acid with glycol. 70 to 100 mol % is introduced by terephthalic acid, and 30 to 0 mol % is introduced by isophthalic acid, naphthalene dicarboxylic acid, adipic acid, sebasonic acid, etc.

The moiety composed of glycol is introduced by ethylene glycol, propylene glycol, tetramethylene glycol, bentamethylene glycol, or hexamethylene glycol, and may be composed of two or more of these types.

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. Specific examples of such polyesters include polyethylene, terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, polyhexamethylene terephthalate, copolymers and mixed polymers thereof, and terephthalic acid of these polymers. 0
Examples include those in which up to 30 mol% is replaced with isophthalic acid. The mixed composition ratio of the saponified Jen-based rubber-modified graft copolymer and polyester described in detail above is preferably 50 to 95 parts by weight of polyester and 5 to 5 parts by weight of saponified graft copolymer.

If the relative amount of polyester is less than 50 parts by weight, the characteristics of polyester will not be exhibited and the original purpose of the polyester composition will be different, which is not preferable. On the other hand, when the amount of saponified diene-based rubber-modified graft copolymer mixed is less than 5 parts by weight, the effect of improving impact resistance is noticeably reduced, and when a fibrous reinforcing agent is further blended, the effect of improving the impact resistance is significantly reduced. Warpage suppression is not sufficient, which is not desirable. In the polyester composition of the present invention having such a blending ratio, the impact resistance of the polyester is greatly improved, and the effect of improving the impact resistance is particularly remarkable when notches are provided.

In addition, a fibrous reinforcing agent can be added to the compound consisting of the above-mentioned polyester and the Jen rubber-modified graft copolymer, if necessary. The anisotropy of the product has been improved,
A remarkable effect is obtained in that warpage does not occur.

Examples of the fibrous reinforcing agent here include glass fiber, asbestos fiber, carbon fiber, etc., and use of glass fiber is particularly preferred. The blending amount of these fibrous reinforcing agents is selected from 0 to 20 parts by weight based on a total of 10 parts by weight of the saponified polyester and hydrogen-based rubber-modified graft copolymer. This is not preferable because other properties such as fluidity deteriorate. The method of mixing polyester, saponified graft copolymer, and fibrous reinforcing agent is not particularly limited, and any commonly known method can be used. A method of melt kneading using an extruder is suitable. It is also possible to add to the compositions of the invention other fillers such as known stabilizer nucleating agents, lubricants, colorants, or glass beads, and antimony trioxide or other flame retardants. etc. can also be mixed. The effects of the present invention will be explained in further detail with reference to Examples below.

Parts and percentages in the examples represent parts by weight and percentages by weight unless otherwise specified. Note that the mechanical properties were measured according to the following standards. Izod impact strength ASTM
-D256-56 tensile strength ASTM-D6
38 Flexural Modulus ASTM-D790-61 Measurement Temperature 2300 Example 1 [Preparation and saponification treatment of graft copolymer] After sealing the reactor equipped with a frame machine, nitrogen introduction pipe, reflux condenser, and thermometer. After purging with nitrogen, the following substances were charged.

(a} Polybutadiene latex (mouth portion) 50.0 Base sodium formaldehyde sulfoxylate
0.40EDTA
O. 10 Ferrous sulfate 0.01 Sodium dodecylbenzenesulfonate 0.5 Sodium phosphate 0.10 (b) Water
180.00 {a)Fi
FRS-2004 type made by Restone (b)
Reactor containing water in polybutadiene latex
After forming a striped pattern, 8 parts of styrene (ST), 2 parts of acrylonitrile (AN), 4 parts of methyl methacrylate (MMA), and 0.0 parts of n-dodecylmercaptan were added while lighting.
Three parts of the mixture were pumped in continuously over a period of 4 hours.

Meanwhile, separately prepared cumene hydroperoxide 0.
A mixture of 3 parts of sodium dodecylbenzenesulfonate, 2 parts of sodium dodecylbenzenesulfonate, and 20 parts of water was continuously pumped in for 5 hours at the same time as the monomer mixture was started. The reaction was stopped after 6 hours. After adding 1 part of di-t-butylhydroxytoluene, the temperature of the graft copolymer latex was increased to 1 part.
The temperature was adjusted to 2,000 ℃, and a solution of 15 parts of sodium hydroxide and 3 parts of water was added to the latex, and the mixture was heated for 8 hours for saponification.

After neutralizing this latex with sulfuric acid, it is coagulated with 5 parts of calcium chloride per 10 parts of polymer, dried, and saponified into a white powdery polybutadiene poly(styrene/methacrylic acid). A methyl/acrylonitrile) graft copolymer was obtained. [Mixing method of polyester and saponified graft copolymer and evaluation of composition] Polytetramethylene terephthalate (relative viscosity at 25oC of 0.5% orthochlorophenol solution rl.70
) and the saponified graft copolymer prepared by the above method were sufficiently dried and mixed in a ratio of 80/20 and 60/40 (weight ratio), and melted and mixed in an extruder with a 4-bar diameter pent. , turned into a beret.

The mechanical properties, mainly impact resistance, of the molded products obtained by vacuum drying and injection molding were investigated as shown in Table 1, and the molded products of this composition were found to have excellent properties. It was found to have impact resistance. Examples 2 and 3 ST/A of monomers graft copolymerized in Example 1
After polymerization and saponification treatment using the same recipe except that the N/MMA ratio was changed as shown below, the compositions were similarly melt-kneaded with polyester and the physical properties of the compositions were measured.

The results are shown in Table 1. ST/AN/MMA Example 2 0/0/50 〃 3 36/9/5 Comparative Example 1 The graft copolymer obtained in Example 1 was not saponified,
Table 1 shows the mechanical properties of the mixture melt-kneaded with polyester in a ratio of 80/20.

The impact resistance was small and there was a clear difference compared to Example 1.
The effect of saponification treatment is obvious. Comparative Example 2 Polybutadiene latex (solid content) 50. Ikaribe acetic acid o. Pentasodium formaldehyde sulfoxylate
2.5 Sodium dodecylbenzenesulfonate 2.0 Water (including water in latex) 200 was charged into a reactor, 5000
After the temperature was raised to 100%, a mixture of 4 parts of styrene, 1 part of acrylic acid, 0.3 parts of n-dodecyl mercaptan, and 0.5 parts of cumene hydroperoxide was added continuously over a period of 3 hours. supplied.

During this time, the temperature was raised to 60q0, and then the latex was
The temperature was raised to 500, and the polymerization was completed by heating for 2 hours.
This graft copolymer latex contains 3 as an oxidative stabilizer.
・After adding 1 part of 5-di-normal rt-butylhydroxytoluene, coagulation with calcium chloride was attempted, but polymer 1
Since no condensation occurred even when 2 base parts were added per 0 base parts, the graft copolymer was recovered by a spread drying method.

The composition was melt-kneaded with polyester in a ratio of 80/20 in the same manner as in Example 1, and the physical properties of the composition were measured.

The results are shown in Table 1. Comparative Example 3 Polytetramethylene terephthalate (PBT, r=1
．． 70), polyethylene terephthalate (PET,
= 1.52) are shown in Table 1.

Example 4 2 parts of the saponified product of the PBD/ST-AN-MMA graft copolymer obtained in Example 1 and 8 parts of polyethylene terephthalate (PET, r = 1.30) were melt-kneaded to obtain a composition. The physical properties of the product were measured and the results are shown in Table 1.

Funatoiri) To K ear ^ day? ＞ ; Hair ○ q A ・ ) Igo'ya) Mozakura 』Samokame to l to say to Szen1tonmimibekoclawmumu -I To small mouth,. Example 5 Using the same apparatus as in Example 1, graft polymerization was carried out using a sub-recipe method.

Butadiene, styrene copolymer latex 75 parts (solid content) (BD/ST=75/25 particle size 0.25)
Glucose 0.5 Sodium pyrophosphate 0.4 Ferrous sulfate 0.05 Water (including water in latex) 150 reactor to 650
After adjusting the temperature to 0, 5 parts of styrene, ethyl acrylate (
EA) 20 parts, tert-dodecyl mercaptan 0.1
5 parts of the monomer temperature mixture was continuously added dropwise over a period of 3 hours, while a mixture of 2.5 parts of potassium oleate, 0.15 parts of cumene hydroperoxide, and 3 parts of water was continuously added dropwise over a period of 4 hours from another charging port. did.

After 6 hours from the start of polymerization, the temperature was raised to 90°C and
-1 part of butylhydroxytoluene was added, and then a solution of 1 part of potassium hydroxide and 3 parts of water was added, followed by saponification treatment by lighting for one hour. The saponified latex was coagulated* in an aqueous solution whose pH was maintained at 2 or below with sulfuric acid, filtered, and dried to obtain a saponified graft copolymer.
The obtained saponified graft copolymer was mixed at a ratio of 2 parts to 10 woven pellets of polytetramethylene terephthalate (Rl. 70), and melt-kneaded using a vented extruder.

Table 2 shows the Izod impact values of test pieces made by injection molding the obtained resin compositions. Examples 6 and 7 In preparing the graft copolymer of Example 5, the amount of polybutadiene-styrene copolymer, the composition of the monomer polymer and its dropping time, soap, initiator, water, composition of the mixture, dropping time and A saponified graft copolymer was obtained by performing the same procedure except for changing the total weight time as shown in Table 2.

Thereafter, in the same manner as in Example 5, a graft copolymer queso compound was blended with polytetramethylene terephthalate so that the ratio of the Jen-based rubber-like polymer in the mixture was 15%, and after melt kneading, injection molding was performed. The Izod impact value was measured. The results are shown in Table 2. Table 2 Example 8
~11 Total amount of saponified graft copolymers obtained in Examples 1 to 3 and 5 with polytetramethylene terephthalate (rl. 45) and glass fiber (Nitto Ori CS)
After uniformly mixing 30 parts of
An 80×3 willow square plate was molded, this square plate was placed on a horizontal plane, and the distance from the horizontal plane to the farthest part was measured as the amount of warpage.

The results are shown in Table 3, and it can be seen that although there is no difference in mechanical properties compared to Comparative Example 2, the amount is small and significantly improved. Example 12 A total of 10 parts of polyethylene terephthalate (RIR l.30) and the saponified graft copolymer obtained in Example 1 were mixed uniformly with 3 parts of glass fiber in the same manner as in Examples 8 to 11. Furthermore, similar physical properties were measured and the results are shown in Table 3.

Comparative Example 4 Table 3 shows the physical properties of a composition consisting of 10 anchors each of polytetramethylene terephthalate and polyethylene terephthalate and 3 glass fiber bases, and it can be seen that the amount of warpage is large.

Table 3 Glass fiber: Nittobo (SX-3P-231) SB
R: Butadiene/styrene (75/25) copolymer Example 13 Polybutadiene latex (solid content) 5
0. Ikaribe vinegar acid o
．． 5-sodium formaldehyde sulfoxylate 2.
5 Sodium dodecylbenzenesulfonate 2.0 Water (including the water in the latex) 200 was charged into a reactor, and after raising the temperature to 50 qo, while bowing, 4 parts of styrene, 1 part of methyl methacrylate, n- A mixture of 0.1 part of dodecyl mercaptan and 0.5 part of cumene hydroperoxide was fed continuously over 3 hours.

During this time, the temperature was raised to 60°C, and then the latex was heated to 65°C.
The temperature was increased to 100 ℃, and the polymerization was completed by heating and floating at sea for 2 hours. This graft copolymer latex contains 3.5% oxidation stabilizer.
After adding 1 part of rt-butylated hydroxytoluene, the temperature of the graft copolymer latex was increased to 120q.
Adjust the temperature to C and add 15% sodium hydroxide to this latex.
A solution of 1 part and 3 parts of water was added thereto and saponified by saponification for 8 hours.

This latex was neutralized with sulfuric acid, coagulated with 5 parts of calcium chloride per 100 parts of polymer, filtered in an oven, and dried to form a white powdered saponified polybutadiene/poly(styrene/methyl methacrylate) graft. A copolymer was obtained. The composition was melt-kneaded with polyester in a ratio of 80/20 in the same manner as in Example 1, and the physical properties of the composition were measured.

The results are shown in Table 4. Table 4

Claims (1)

[Claims] 1 A (a) In the presence of 20 to 90 parts by weight of a diene-based rubbery polymer, (b) 5 to 100% by weight of an α/β-unsaturated carboxylic acid ester monomer and an aromatic vinyl monomer and a graft copolymer obtained by emulsion graft polymerization of 80 to 10 parts by weight of a monomer or monomer mixture consisting of 90 to 0% by weight of one or more vinyl monomers selected from vinyl cyanide monomers. A saponified diene-based rubber-modified graft copolymer obtained by saponifying a polymer, B a thermoplastic polyester resin, and C a fibrous reinforcing agent for a total of 100 parts by weight of A5-50 parts by weight and B95-50 parts by weight. A thermoplastic polyester resin composition containing C in a proportion of 0 to 200 parts by weight.