JPH01306462A - Resin composition for connector - Google Patents

Abstract

PURPOSE:To provide the title resin composition outstanding in soldering heat resistance, comprising a polyethylene terephthalate-based resin blend, metal salt of copolymer from alpha-olefin and alpha,beta-unsaturated carboxylic acid, brominated polystyrene and glass fiber. CONSTITUTION:The objective composition comprising (A) 100 pts.wt. of a resin blend comprising A1: 95-5 pts.wt. of a polyethylene terephthalate resin and A2: 5-95 pts.wt. of a block copolymer containing 60-97wt.% of ethylene terephthalate-based segment and 3-40wt.% of polyether segment containing 2-30wt.% of said polyether segment, (B) 0.04-10 pts.wt. of a metal salt of copolymer from alpha-olefin and alpha,beta-unsaturated carboxylic acid (pref. Na salt of copolymer from ethylene and methacrylic acid), (C) 5-50 pts.wt. of a brominated polystyrene, and (D) 15-70 pts.wt. of glass fiber (pref. chopped strand).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a resin composition for connectors that can produce connectors that have good solder heat resistance, a large holding force for the inserted bottle, and good electrical properties. Regarding.

[Prior art/issues to be solved by the invention] Many of the connectors that have been used in the past are made of glass made of reinforced polybutylene terephthalate compositions (hereinafter referred to as reinforced PBT compositions) or plasticizers. Transition point T. It is manufactured from a modified reinforced polyethylene terephthalate based composition (hereinafter referred to as modified reinforced PBT based composition) which is obtained by reinforcing a modified polyethylene terephthalate based composition with a lower carbon content with glass fibers.

However, although connectors made from reinforced PBT compositions have a high retention force for driven pins, they do not have sufficient solder heat resistance, and are subject to deformation or rough surfaces when immersed in a solder bath. If the temperature of the solder bath is lowered to solve this problem, the product must be immersed in the solder bath for a long time, resulting in a decrease in productivity.

On the other hand, for connectors made from modified and reinforced PET compositions,
There is a problem that the toughness is not sufficient, so it is easy to break when a pin is driven in, and the volume resistivity value vR after moist heat treatment is also insufficient.

[Means for Solving the Problems] The present invention has been made to solve the problem that conventionally used connectors are not necessarily satisfactory as described above, and includes: (A) [1] Polyethylene terephthalate resin 95~
5 parts (by weight, the same applies hereinafter) and ■60 to 97% of ethylene terephthalate segments (
weight%, the same applies hereinafter) and polyether segment 3 to 40
% and a block copolymer containing 5 to 95 parts, and a polyether segment content of 2 to 3
0% polyethylene terephthalate resin mixture 1
00 parts, (B) 0.04 to 10 parts of a metal salt of a copolymer of α-olefin and α,β-unsaturated carboxylic acid, (C) 5 to 50 parts of brominated polystyrene (D) Glass fiber (chotu) pud strand) 15-70
The present invention relates to a resin composition for connectors consisting of parts.

[Example] The polyethylene terephthalate resin referred to herein refers to one containing at least 90 mol% of terephthalic acid or its ester-forming ability as an acid component, and ethylene glycol or its ester-forming ability as a glycol component. At least 90 mol% of derivatives with
It is a linear saturated polyethylene terephthalate resin obtained using

The acid components other than terephthalic acid and its derivatives having ester forming ability used in the range of less than 10 mol% include other aromatic dicarboxylic acids having 8 to 14 carbon atoms, aliphatic dicarboxylic acids having 4 to 8 carbon atoms; , even carbon number 8-12
Specific examples include phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, adipic acid, sebacic acid, cycloaliphatic dicarboxylic acid, etc. Examples include dicarboxylic acid.

In addition, the diol component other than ethylene glycol used in the range of less than 10 mol% has a carbon number of 3 to 1
Examples include aliphatic diols having O, alicyclic diols having 6 to 15 carbon atoms, and aromatic diols having 6 to 15 carbon atoms. Specific examples include propane-1,3
~Diol, butane-1,4-diol, pentane-1
,5-diol, hexane-1,6-diol, cyclohexane-1,4-dimetatool, 2,2-dimethylpropane-1,3-diol, 2,2-bis(4'-hydroxycyclohexyl)propane, 2, 2-screw (4°
Examples include -hydroxyphenyl)propane and hydroquinone.

Polyethylene terephthalate resin produced from the above components usually has an intrinsic viscosity of 0.835 to 1.20 (
Phenol/1,1.2.2-tetrachloroethane-
50150 (weight ratio), 0.5% concentration, 25°C, hereinafter the same), but from the point of view of improving the balance between crystallization rate and mechanical strength, the solid a viscosity is 0.5%.
40 to 0.70 is preferred, and 0.45 to 0.65
More preferred is

In this specification, the ethylene terephthalate segment refers to a polyethylene terephthalate resin oligomer, which typically includes a polyethylene terephthalate oligomer manufactured from the same raw materials as those constituting the polyethylene terephthalate resin, and a polyethylene terephthalate resin oligomer made from the polyethylene terephthalate resin. A segment (a segment whose terminal end is ~CO-), and a polyether segment is a polyether segment of the general formula (I); Divalent group, Q is 5 to 4
(the integer 0, the two R1s do not have to be the same) (the part of the polyether excluding the terminal end).

Specific examples of R1 include ethylene, propylene, isopropylene, butylene, and bisphenol A.
Among the polyether segments represented by general formula (11), segments from polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc., and general formula (■): (wherein, R2 is 02 to C4 The divalent hydrocarbon group, X, is
For example, in a divalent bonding group such as -〇(CH3)2-, -3O2-, -Co-, m and n are each an integer of 5 to 15, (m+n) R2 do not need to be the same). The represented segments and the like are preferable from the viewpoint of increasing the crystallization rate of the resulting composition and improving injection moldability.

In the present invention, at least one of the ethylene terephthalate segments is contained in an amount of 60 to 97%, preferably 60 to 97%.
Block copolymers containing from 5 to 90% and from 3 to 40%, preferably from 10 to 35% of at least one polyether segment are prepared and used.

The content of the ethylene terephthalate segment is 0.
If it is less than 0%, the thermal stability of the block copolymer will be poor, making it difficult to handle; if it exceeds 97%, a sufficient crystallization promoting effect can be expected at an economically attractive mixing ratio. Both are unfavorable.

The block copolymer produced in this way is usually 0
．． Although it has an intrinsic viscosity of 40 to 1.20, it is preferable to have an intrinsic viscosity of 0.50 to 1.00 from the viewpoint of improving the crystallization rate and mechanical strength in a well-balanced manner.

The block copolymer may be manufactured by copolymerizing in a polyester synthesis reaction vessel or by copolymerizing in an extruder. - In the present invention, 95 to 5 parts of the polyethylene terephthalate resin, preferably 95 to 2 parts
5 parts and 5 to 95 parts of block copolymer, preferably 5 to 7 parts
5 parts and polyether segment content from 2 to 30%,
Preferably, 100 parts of a polyethylene terephthalate resin mixture (component (A)) having a molecular weight of 3 to 1,596 is prepared.

If the proportion of the polyethylene terephthalate resin exceeds 95 parts, the crystallization promoting effect will be insufficient, and if it is less than 5 parts, it will be economically unattractive. Furthermore, if the polyether segment content is less than 2%, the effect of promoting crystallization will be insufficient, and if it exceeds 30%, although crystallization will be sufficiently promoted, mechanical properties will tend to deteriorate, and thermal stability will also be affected. A problem arises.

The metal salt of the copolymer of α-olefin and α,β-unsaturated carboxylic acid used in the present invention is a component used as a nucleating agent, and the copolymer forming the metal salt includes, for example, ethylene , α-olefins such as propylene7
α of acrylic acid, methacrylic acid, maleic anhydride, itaconic acid, etc. from 0 to 99.5 mol%, and further from 90 to 98 mol%.

A preferred example is one copolymerized with 0.5 to 30 mol %, preferably 2 to 10 mol % of β-unsaturated carboxylic acid.

Further, as the metal forming the metal salt, any monovalent to trivalent metal can be used without particular limitation, but alkali metals such as sodium or potassium, and alkaline earth metals such as calcium and magnesium are preferable. .

Furthermore, it is preferable that 5 mol% or more, more preferably 10 mol% or more of the carboxyl groups in the copolymer be metal salts.

Among the metal salts of copolymers of α-olefins and α,β-unsaturated carboxylic acids, sodium salts of copolymers of ethylene and methacrylic acid (Himilan ■ (manufactured by Mikata DuPont Polychemicals ■) Particularly preferred are those commercially available as .

Brominated polystyrene, which is the component (C) used in the present invention, is a component used as a flame retardant and a nucleating agent, and can be used without particular limitation as long as the bromine content is about 30% or more. A polystyrene bromide or a mixed polymer of styrene tribromide and styrene tribromide with a content of 50 to 75% is preferred.

Glass fiber, which is the component (D) used in the present invention, is a component used to impart appropriate rigidity to the resin composition and raise the heat deformation temperature to a practical level, and is a component used to improve moldability, surface properties, etc. For example, the average diameter is 7 to 13, and the length is
A preferred example is a chopped strand of about 0.05 to 50 mm.

0.04 to 0.04 parts of component (B) per 100 parts of component (A)
10 parts, preferably 2.5 to 6 parts, component (C) 5 to 50 parts
parts, preferably 10 to 25 parts and (D>component 15 to 7
The composition of the invention is prepared from 0 parts, preferably from 25 to 60 parts.

If the proportion of the component (B) is less than 0.04 part, the crystallization of the resin will be slow, resulting in insufficient mechanical properties and heat resistance, as well as increased fluidity, which will cause paris during molding. Moreover, if it exceeds 10 parts, the melting point will drop significantly, and P
Not only does the solder heat resistance, which is a characteristic of ET resins, decrease, but also the volume resistivity decreases significantly during moist heat treatment.

Further, if the proportion of the component (.C) is less than 5 parts, the flame retardance will be insufficient, and if it exceeds 50 parts, the material will become brittle and the yield during bottle stamping will be significantly reduced.

Furthermore, if the proportion of component (D) is less than 15 parts, not only will crystallization be slow, but even if crystallized, sufficient rigidity will not be obtained.
The pin retention force also decreases significantly due to creep. Also 7
If it exceeds 0 parts, it will be difficult to form a molded product with a surface appearance at a practically acceptable level, and the rigidity will become too large, resulting in too much resistance when driving the bottle.
Cracks during driving may increase.

The resin composition of the present invention may further contain other components, such as flame retardants such as antimony trioxide, antioxidants, colorants, plasticizers, etc., as necessary. For example, in the case of antimony trioxide, 1/2 of brominated polystyrene
Flame retardancy can be improved by adding in an amount equivalent to 4 to I/3 weight.

The composition of the present invention obtained in this way is a mixture of specific components in a specific ratio, and such a composition can be molded by a conventional method such as injection molding and driven with a pin. can be made into a connector. The resulting connector has good solder heat resistance, has a large holding force for the inserted bottle, and has a large volume resistivity after moist heat treatment (95% RH x 40°C x 720 hours later
SΩ・011 or higher), resulting in a highly reliable product.

Furthermore, the heat resistance (HD T ) of a molded article, for example, 1116 inches thick, made from the resin composition of the present invention is high, and is good at 170° C. or higher when the glass fiber content in the composition is 30%.

Next, the composition of the present invention will be specifically explained based on Examples.

Example 1 Block copolymer (hereinafter referred to as block copolymer) consisting of 70% ethylene terephthalate segments and 30% ethylene oxide addition polymer of bisphenol A (weight ratio of bisphenol A and ethylene oxide 1:17, average molecular weight ff1lo00) 792g of polyethylene terephthalate with an intrinsic viscosity of 0.61 measured at 25°C in a mixed solvent of phenol and 1.1,2.2-tetrachloroethane, 3188g of brominated polystyrene (trade name: Baiguchi Check 88PB) , manufactured by Ferro Corporation) 900g, copolymer of ethylene and unsaturated carboxylic acid and its sodium salt (trade name:
Himilan, Mikata, manufactured by DuPont Polychemical ■) 150
After thoroughly mixing 55 g of stabilizer (trade name Nijinox 4128, manufactured by Cipro Kasei ■), 7 g of glycidoxypropyltrimethoxysilane, and 180 g of antimony trioxide in a ribbon blender, The mixture was melt-kneaded using an extruder PCM 45 to obtain a pelletized composition. At this time, glass fibers (chopped strands with a diameter of 10 μm and a length of 3 mm) were kneaded in the middle of the twin-screw extruder, so that the glass fiber content in the composition was 30 μm.
%.

After drying the resulting pellet at 140°C for 4 hours, injection molding was performed at a mold temperature of 60-65°C to give a diameter of 1.39~.
1.40 mm holes arranged in 3 rows of 11 holes at 2.54 mm intervals, 30 In 111 square, 2 am thick.
A plate-shaped molded product (hereinafter referred to as a socket plate) and a test piece for thin-walled HDT (2) with a length of 127 ma+, a width of 12.7 mm, and a thickness of 1/16 inch were prepared. The pin insertion force, pin retention force, and pin retention force after solder immersion were measured.The results are shown in Table 1.

(Thin-walled HDT) Using a test piece for HDT made up of four test pieces for thin-walled HDT (b), the heating deformation temperature (HDT, load 18.8 kg/C
I) is measured.

(Bin insertion force) For each type of socket plate, use a universal testing machine to insert one IC socket pin (see Figure 1) whose maximum diameter of the part to be embedded in the socket plate is 1.50fflllφ. Push in and measure the maximum resistance force during this time. Note that the unit of numerical values in FIG. 1 is ff1ffl.

(Pin retention force) After driving the pins into the socket board, leave it in a constant temperature and humidity room at a temperature of 23℃ and relative humidity of 50% for a day and night, and then push the inserted bottle out from the opposite side with a cylindrical jig. The maximum resistance force is measured using a universal tensile tester.

(Pin retention force after immersion in solder) After immersing the socket plate into which the IC socket bottle was pushed in as described above in a solder bath at 270±5°C for 10 seconds, the inserted pin was held in place using a cylindrical jig. The maximum resistance force when pushing and pulling out from the opposite side is measured using a universal tensile tester. Immersion into the solder bath was performed according to Monthly SC5034.

Comparative Example 1 A socket plate and a thin-walled HDT test piece were prepared in the same manner as in Example 1 except that 792 g of polyethylene terephthalate resin was used instead of 792 g of the block copolymer.
evaluated. The results are shown in Table 1. The surface of the socket after being dipped in solder was extremely rough, making it impractical.

Comparative Example 2 A socket plate and a thin-walled 11DT test piece were produced and evaluated in the same manner as in Example 1 except that glass fiber was not added. The results are shown in Table 1.

[Margins below] Table 1 [Effects of the Invention] When a connector is manufactured using the composition of the present invention, a connector with high solder heat resistance, high heat resistance, and high holding power for the inserted bottle can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a side view of the IC socket pin used in Example 1. Patent applicant: Kanekabuchi Chemical Industry Co., Ltd.

Claims (1)

[Claims] 1(A) [1] Polyethylene terephthalate resin 95
~5 parts by weight and [2] ethylene terephthalate segment 60-97
and 5 to 95 parts by weight of a block copolymer containing 3 to 40 weight % of polyether segments, and the polyether segment content is 2 to 3.
(B) 0.04 to 10 parts by weight of a metal salt of a copolymer of α-olefin and α,β-unsaturated carboxylic acid; (C) Brominated 5 to 50 parts by weight of polystyrene and (D) glass fiber (
A resin composition for connectors comprising 15 to 70 parts by weight of chopped strands.