JPH01103649A - Reinforced thermoplastic polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. having excellent mechanical characteristics, heat resistance, resistance to cooling-heating cycle, by adding a needle-shaped TiO2 to a thermoplastic polyester. CONSTITUTION:1-250pts.wt. needle-shaped TiO2 whose average length (l) of the minor axis is 0.01-0.5mum, length (d) of the major axis is 0.05-20mum and l/d is 3-200 and, if necessary, a rubber component (e.g., ethylene/glycidyl methacrylate copolymer), a reinforcing material, a filler, a releasing agent, a nucleating agent, flame-retardant, etc. are compounded in 100pts.wt. thermoplastic polyester whose intrinsic viscosity measured in 0.5% o-chlorophenol soln. at 25 deg.C is 0.36-1.60.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a novel filler-containing reinforcing material that can provide molded products with excellent mechanical properties and thermal properties, and particularly excellent cold and heat cycle resistance. The present invention relates to a polyester resin composition.

<Conventional technology> Thermoplastic polyester resins, such as polyethylene terephthalate and polybutylene terephthalate, have excellent mechanical properties, heat resistance, chemical resistance, weather resistance, etc., and can further improve strength and strength by adding reinforcing materials and fillers. The positivity has been greatly improved and it is widely used in fields such as electrical equipment, automobiles, and building materials. Among these, thermoplastic polyester resins reinforced with mu-shaped reinforcements (e.g., glass @ fiber, carbon fiber, metal fiber, etc.) and whisker-like reinforcements (e.g., alumina whiskers, silicon carbide whiskers, potassium titanate whiskers, etc.) is a molded product made by insert molding metal parts, etc., and is used as a variety of industrial functional parts due to its toughness.

However, in molded products with metal parts inserted, cracks occur in the resin at the contact area between the metal and resin due to thermal shock (thermal shock caused by repeated cold-heat cycles) due to the difference in thermal expansion coefficient between the metal and the resin. There was a drawback. As a means to improve these, the surface of the reinforcing material can be coated with a coupling agent (
For example, a method of treating the thermoplastic polyester with a coupling agent such as silane, titanate, or zircoaluminate to improve the affinity between the reinforcing material and the resin, or adding an epoxy compound to the thermoplastic polyester to bond the thermoplastic polyester to the insert metal. Known methods include improving the adhesion between parts and blending a rubber component into thermoplastic polyester to improve the impact resistance of the resin.

On the other hand, it is disclosed in Japanese Patent Publication No. 46-7180, Japanese Patent Application Laid-Open No. 51-28141 and Japanese Patent Application Laid-Open No. 61-72050 that granular titanium oxide is blended with polyethylene terephthalate.
It is disclosed in the publication No.

Problems to be Solved by the Present Invention> However, the method of treating the surface of the reinforcing material with a coupling agent and the method of adding an epoxy compound or the like to thermoplastic polyester have a poor effect on improving cold and heat cycle resistance. Although the method of blending a rubber component with the thermoplastic polyester can provide a certain degree of cold and hot cycling resistance, it is not only insufficient, but also has the problem that heat resistance and rigidity decrease and do not reach a substantially effective level. .

Furthermore, when granular titanium oxide is blended with polyethylene terephthalate, molded products with metal parts inserted therein have the problem that cracks occur in the resin at the contact area between the metal and the resin due to thermal shock, resulting in destruction.

The present invention aims to solve such problems.
1. The present invention has been achieved as a result of extensive research in order to obtain a reinforced thermoplastic polyester resin composition that has good mechanical properties, good heat resistance, and particularly excellent thermal cycle resistance.

Means for Solving the Problems> That is, the present invention is directed to thermoplastic polyester 100. The thermoplastic polyester used in the present invention is a polymer or copolymer obtained by a condensation reaction mainly consisting of a dicarboxylic acid (or its ester-forming derivative) and a diol (or its ester-forming derivative). .

Examples of the dicarboxylic acids include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 1.5
-Naphthalenedicarboxylic acid, bis(p-carboxyphenyl)methane, anthracenedicarboxylic acid, 4.4゛-
Aromatic dicarboxylic acids such as diphenyl ether dicarboxylic acid and 5-sodium sulfoisophthalic acid; aliphatic dicarboxylic acids such as adipic acid, sebacic acid, azelaic acid, and dodecanedioic acid; 1°3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. Examples include alicyclic dicarboxylic acids such as acids and ester-forming derivatives thereof. In addition, the diol component has 2 carbon atoms.
~20 aliphatic glycols, namely ethylene glycol, propylene glycol, 1,4-butanediol,
Neopentyl glycol, 1,5-bentanediol,
1.6-hexanediol, decamethylene glycol,
Cyclohexane dimetatool, cyclohexanediol, etc., or long chain glycols with a molecular weight of 400~e, ooo, i.e. polyethylene glycol, poly-1,
Examples include 3-propylene glycol, polytetramethylene glycol, and ester-forming derivatives thereof. Preferred specific examples of these polymers or copolymers include polybutylene terephthalate, polybutylene (terephthalate/isophthalate), polybutylene (terephthalate/adipate), polybutylene (terephthalate/separate), polybutylene (terephthalate/decane dicarboxylate), Polyethylene terephthalate, polyethylene (terephthalate/isophthalate), polyethylene (terephthalate/adipate),
Polybutylene (terephthalate 15-sodium sulfoisophthalate), polyethylene (terephthalate 15-sodium sulfoisophthalate)
-sodium isophthalate), etc.; polybutylene terephthalate, polybutylene (terephthalate/adipate), polybutylene (terephthalate/adipate),
Polybutylene (terephthalate/decane dicarboxylate), polyethylene terephthalate, polyethylene (
Terephthalate/adipate) and the like are particularly preferably used. In addition, these thermoplastic polyesters have an intrinsic viscosity of 0.36 to 1.60, especially 0.52 to 1.3 when a 0.5% 0-chlorophenol solution is measured at 25°C.
A value in the range of 5 is preferred.

If the intrinsic viscosity is less than 0.36, the mechanical properties are poor;
Furthermore, if the intrinsic viscosity exceeds 1.60, moldability will be poor, which is not preferable. The titanium oxide used in the present invention is different from the granular titanium oxide commonly used in conventional pigments, and is acicular, with an average short axis diameter of 0.01.
~0.5 μm, long sleeve length in the range of 0.05 to 20 μm, length of major axis/average diameter of short axis +! Titanium oxide having an acicular shape with /d) of 3 to 200 is preferred.

The acicular titanium oxide preferably has an L/d of 10 or more, and more preferably has an L/d of 30 or more. If the ld is less than 3, the effect of improving cold and hot cycle resistance is similar to that of granular titanium oxide for pigments. If the average 1/d exceeds 200, the thermoplastic polyester resin will have poor fluidity when melted, which is not preferable.

The amount of the acicular titanium oxide added is 1 to 250 parts by weight, preferably 3 to 150 parts by weight, and more preferably 6 to 100 parts by weight, based on the thermoplastic polyester.

If the amount added is less than 1 part by weight, no effect of improving cold/heat cycle resistance can be expected, and if it exceeds 250 parts by weight, the impact resistance will decrease, which is undesirable. It can also be used after being treated with a silane coupling agent, a zircoaluminate coupling agent, a titanate coupling agent, etc. Although the principle by which molded articles obtained from the composition of the present invention exhibit extremely excellent cold and heat cycle resistance has not yet been fully elucidated, the affinity between the interface between the acicular titanium oxide and the thermoplastic polynisder Because it is much better than potassium titanate, it is less likely to break at the interface between the reinforcing material and the resin due to thermal shock than with glass fiber or potassium titanate, and therefore has excellent cold and heat cycle resistance. It is estimated that the Furthermore, the composition of the present invention can further improve its cold and heat cycle resistance by using various rubber components in combination. In particular, such rubber components include (i) an epoxy group-containing copolymer consisting of an α-olefin and an epoxy group-containing unsaturated monomer, and (ii) an unmodified copolymer consisting of ethylene and an α-olefin having 3 or more carbon atoms. 0.01 to 10 for ethylene copolymer
Modified ethylene copolymer (i i i) obtained by grafting % by weight of unsaturated carboxylic acid or its derivative
Hydrogenated mana is 0.01 to 10% of the block copolymer of unhydrogenated co-immersed diene and aromatic vinyl, or the block copolymer.
Modified block copolymers obtained by grafting % by weight of unsaturated carboxylic acids or derivatives thereof can be preferably used. To give specific examples of these rubber components, preferred examples of the epoxy group-containing copolymer (1) include ethylene/glycidyl methacrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, and ethylene/methyl methacrylate copolymer. /glycidyl methacrylate copolymer, ethylene/glycidyl acrylate copolymer, ethylene/vinyl acetate/glycidyl methacrylate copolymer, ethylene/glycidyl ether copolymer, among others, ethylene/glycidyl methacrylate copolymer is most preferred. Furthermore, together with the epoxy group-containing copolymer (i),
If an ethylene copolymer consisting of ethylene and an α-olefin having 3 or more carbon atoms and/or a diene copolymer consisting of ethylene, an α-olefin having 3 or more carbon atoms, and a non-conjugated diene are used together, impact resistance can be improved. It can be further improved. Specific examples of these copolymers include ethylene/
Propylene copolymer, ethylene/butene-1 copolymer,
Ethylene/pentene-1 copolymer, ethylene/propylene/butene-1 copolymer, ethylene/propylene 15-
Ethylidene-2-norbornene copolymer, ethylene/propylene/1,4-hexadiene copolymer, ethylene/
propylene/dicyclopentanediene copolymer, etc., of which ethylene/propylene copolymer and ethylene/butene-1 copolymer are preferred;
) modified ethylene copolymers include ethylene/propylene copolymer, ethylene/butene-1 copolymer, ethylene/propylene/dicyclopentanene copolymer, and ethylene/propylene 15-ethylidene-2-norbornene copolymer. Unsaturated carboxylic acids or derivatives thereof, such as maleic acid, fumaric acid, glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, diglycidyl itaconate, to unmodified ethylene copolymers such as polymers.
Diglycidyl citraconate, diglycidyl butene dicarboxylate, diglycidyl tetrahydrophthalate, maleic anhydride, itaconic anhydride, citraconic anhydride, maleic acid imide, itaconic acid imide, citraconic acid imide, glycidyl methacrylate, maleic anhydride, anhydrous Preferred examples include modified ethylene copolymers that are graft-reacted with itaconic acid, maleic acid imide, etc. Specific examples include maleic anhydride grafted ethylene/propylene copolymers and maleic anhydride grafted ethylene/butene-1 copolymers. Preferred are polymers, glycidyl methacrylate grafted ethylene/propylene copolymers, glycidyl methacrylate grafted ethylene/butene-1 copolymers, etc.
In addition, as the block copolymer (iii) above, 1.3
- Conjugated dienes such as butadiene, isoprene, 1,3-pentadiene and styrene, α-methylstyrene, 0-
Hydrogenated and block copolymers made of aromatic vinyl hydrocarbons such as methylstyrene, p-methylstyrene, 1,3-dimethylstyrene, and vinylnaphthalene, and preferred specific examples are hydrogenated or unhydrogenated styrene/block copolymers. Butadiene/styrene triblock copolymers, hydrogenated or unhydrogenated styrene/isoprene/styrene triblock copolymers, etc. Among them, styrene/butadiene/styrene triblock copolymers are hydrogenated from the viewpoint of heat resistance. More preferably used. In addition, as the modified block copolymer, as mentioned above in the section of the modified ethylene copolymer in (11), those obtained by grafting unsaturated carboxylic acids and derivatives thereof are particularly preferably used. 0 The composition of the present invention may contain reinforcing materials and fillers other than acicular titanium oxide, such as glass fibers, carbon fibers, metal fibers, silicon carbide whiskers, potassium titanate whiskers, and gypsum, to the extent that the effects of the present invention are not impaired. Fiber, mica, talc, calcium silicate (wallastenite), kaolin, clay,
Calcium sulfate, calcium carbonate, silicon oxide, titanium oxide (granular), etc. may also be used in combination.The composition of the present invention may contain thermoplastic polyester nucleating agents (e.g., sodium stearate, barium stearate, sodium montanate, metal salts of organic carboxylic acids such as barium montanate, partial sodium or barium salts of montanic acid esters, sodium benzoate, sodium or barium salts of tere or isophthalate, ionomers, talc, etc.) and also crystallization promoters (e.g. polyethylene glycol). , polyalkylene glycol derivatives such as polyethylene glycol dibenzoate, neopentyl glycol dibenzoate, polyethylene glycol bis(2-ethylhexanoate), benzoic acid esters, polylactones, N-substituted toluyl sulfonamide, etc.). Various other additives may be added to the composition of the present invention, such as release agents such as montanic acid wax, polyethylene wax, and silicone oil, flame retardants, heat stabilizers, ultraviolet absorbers, pigments, and dyes. be able to. In addition, small amounts of other thermoplastic resins (e.g. polyethylene, polypropylene, polystyrene, acrylic resins, fluorine resins, polyamides, polyacetals, polycarbonates, polysulfones, polyphenylene sulfides, polyphenylene oxides, etc.), thermosetting resins (e.g. phenolic resins, 5 melamine resins, Polynisder resin, silicone resin, epoxy resin, etc.), soft thermoplastic resin (e.g., ethylene/vinegar copolymer, polyester elastomer, etc.) may also be added.The method for producing the composition of the present invention is not particularly limited. However, for example, there is a method in which thermoplastic polyester, acicular titanium oxide, and other additives are blended together as needed, and the raw materials are fed to a screw extruder and melt-kneaded. is supplied and melted, and the other supply [
The reinforced thermoplastic polyester resin composition of the present invention can be used by injection molding, etc. A desired molded product can be formed by any molding method such as extrusion molding, blow molding, and vacuum molding.

<Example> The effects of the present invention will be further explained below with reference to Examples. In addition, parts in Examples mean parts by weight, and abbreviations mean the following.

PET: Polyethylene terephthalate PBT: Polybutylene terephthalate BSL Barium nistearate NPC-DB: Neobentyl glycol dibenzoate Examples 1-3. Comparative Examples 1 to 11 Polybutylene terephthalate 10 with an intrinsic viscosity of 0.83
0 parts by weight, various reinforcing materials or fillers shown in Table 1 were blended in the proportions shown in Table 1, and the temperature was set at 250°C.
The mixture was melt-kneaded into pellets using a vented extruder with a single screw of 0 rmφ.

After drying the pellets of the obtained composition at 130°C for 5 hours,
Using a screw in-line injection molding machine with a mold clamping pressure cuff of 5 tons set at 250°C, a molded product for thermal cycle testing equipped with an insert fitting was molded at a mold temperature of 80°C. 1 hour → -40℃×1
The cold and hot cycle resistance was evaluated by calculating the number of times the molded product was repeatedly subjected to cold and hot cycles until cracks appeared. FIG. 1 is a plan view of the above molded product, and the second
The figure is a cross-sectional view of the same molded product. The molded product consists of a cylindrical insert fitting 1 and a resin part 2.
The entire surface of the molded product is covered with a resin part 2, and the upper surface of the molded product is covered with a hole 3 formed by a support that supported the insert fitting 1 in the mold.
is formed. In addition, the above dried pellet was heated to 250°C.
Using a risk screw in-line injection molding machine with a mold clamping pressure of 50 tons and a mold temperature of 80℃, a 172" width 1z
od street impact test piece and...rob test piece (172″ x 174
″×5″) was molded. Using the obtained test piece, Iz
od street attack test IVj! (based on ASTH0256) and bending test (based on ASTH0790) were conducted to evaluate mechanical properties. In addition, the appearance of the molded product was visually observed. The results are shown in Table 1.

The first fact is that polybutylene terephthalate containing acicular titanium oxide has better cold and heat cycle resistance than polybutylene terephthalate containing other reinforcing materials and fillers.
This is clear from the table.

Examples 4-6, Comparative Examples 12-22 Polyethylene terephthalate 510 with an intrinsic viscosity of 0.60
The proportions shown in Table 2 of various reinforcing materials or fillers shown in Table 2 and barium stearate and neopentyl glycol dibenzoate as a crystal nucleating agent and crystallization accelerator for polyethylene terephthalate, respectively, based on the 0 weight part. The mixture was melt-kneaded into pellets using a vented extruder equipped with a 40φ single screw set at 280°C.

After drying the pellet of the obtained composition at 150°C for 5 hours, it was subjected to a cooling cycle in the same manner as in Example 1 at a mold temperature of 130°C using a screw in-line injection molding machine with a mold clamping pressure cuff of 5 tons set at 280°C. A molded product for testing and a test piece for evaluating mechanical properties were molded, and then cold and heat cycle resistance, mechanical properties, and appearance of the molded product were evaluated. Second result
Shown in the table. It is clear from Table 2 that the cold and hot cycle resistance of polyethylene terephthalate blended with acicular titanium oxide is superior to polyethylene terephthalate blended with other reinforcing materials and fillers.

<Effects of the Invention> Molded articles obtained from the composition of the present invention have excellent mechanical properties and thermal properties, particularly cold and hot cycle resistance, and are therefore effective as functional parts such as automobile parts.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the molded product molded in the example, and the second
The figure is a cross-sectional view of the same molded product. 1...Insert fitting 2...Resin part 3...Hole

Claims (1)

[Claims] A reinforced thermoplastic polyester resin composition containing 1 to 250 parts by weight of acicular titanium oxide based on 100 parts by weight of thermoplastic polyester.