JP3107451B2 - Antistatic agent for polycarbonate resin and polycarbonate resin composition containing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an antistatic agent for a polycarbonate resin and a polycarbonate resin composition containing the same. Polycarbonate resin is a resin having excellent transparency, and is widely used for various applications by utilizing its properties. However, the polycarbonate resin is easily charged like other thermoplastic resins, and dust and dirt are easily attached due to the charging. The adhesion of dust and dirt on the polycarbonate resin significantly reduces its commercial value because of its transparency. Therefore, there is a strong demand for polycarbonate resins to prevent static electricity while making use of its characteristic transparency. The present invention relates to an antistatic agent for a polycarbonate resin which satisfies such a demand, and a polycarbonate resin composition containing the same.

[0002]

2. Description of the Related Art Conventionally, a method applied to many other thermoplastic resins has been used to prevent the electrification of a polycarbonate resin. For example, 1) an example using an inorganic conductive substance such as carbon black or metal powder, and 2) an example using a sulfonic acid type anionic surfactant such as an alkyl sulfonate or an alkylbenzene sulfonate (Japanese Patent Laid-Open No. Sho 5)
6) 24442, JP-A-63-230764), 3) Examples using polyethers such as polyethylene oxide and polyoxyethylene-polyoxypropylene glycol ether (JP-B-55-4141). 4) Conjugated dienes and polyalkylene glycols Copolymer with acrylate,
Examples of using a graft copolymer obtained by graft-polymerizing a vinyl monomer onto a copolymer of a conjugated diene and a polyalkylene glycol acrylate (JP-A-55-36237); polyoxyalkylene glycols such as polyoxyalkylene ether ester amide; Examples include using a block copolymer or a graft copolymer having a block. However, these conventional examples have inherent properties of the polycarbonate resin due to the inorganic conductive substance used or the poor compatibility or dispersibility of the compound to be used and the polycarbonate resin. It has the disadvantage of impairing transparency and also impairing other physical properties.

[0003]

The problem to be solved by the present invention is that in the prior art, it is not possible to prevent the electrification while taking advantage of the physical properties inherent in the polycarbonate resin, particularly transparency.

[0004]

Means for Solving the Problems Thus, the present inventors have
As a result of intensive studies from the above viewpoints, as an antistatic agent for a polycarbonate resin, a polyoxyalkylene block and a polyoxy 1,2-alkylene ether-1,
It has been found that it is correct and suitable to use a block copolymer having a specific structure having a 2-alkylene carbonate block.

That is, the present invention relates to a polyether (poly) ol having 1 to 6 hydroxyl groups and a polyoxyalkylene block composed of an oxyalkylene unit having 2 to 4 carbon atoms in the molecule. A block copolymer obtained by ring-opening polymerization of a carbonate, wherein polyoxyalkylene block / polyoxy 1,2-alkylene ether-1,2-alkylene carbonate block of the following A = 10/90 to 90/10 (weight ratio) The present invention relates to an antistatic agent for a polycarbonate resin, comprising a block copolymer having a number average molecular weight of 5,000 to 100,000 having a ratio of: The present invention also relates to a polycarbonate resin composition comprising the above-mentioned antistatic agent for polycarbonate resin in a proportion of 1 to 30 parts by weight with respect to 100 parts by weight of the polycarbonate resin.

A: Polyoxy 1,2-alkylene ether-1,2-alkylene carbonate block composed of one or more units represented by the following formula 1:

[0007]

(Equation 1)

In the formula 1, X ¹ and X ^{2 are} ethylene groups or ethylene groups which are simultaneously substituted by the same or different hydrocarbon groups having 1 to 6 carbon atoms.

In the block copolymer used as the antistatic agent for the polycarbonate resin of the present invention, the polyoxyalkylene block is composed of oxyalkylene units having 2 to 4 carbon atoms. Examples of the polyoxyalkylene block include: 1) a polyoxyalkylene block composed of a single oxyalkylene unit such as a polyoxyethylene block, a polyoxypropylene block, or a polyoxybutylene block; 2) two or more different oxyalkylenes There is a mixed polyoxyalkylene block in which units are combined in random or block form.
As such a polyoxyalkylene block, one having 75 mol% or more of oxyethylene units is preferable,
More preferably, it is 100 mol%. The number average molecular weight is preferably from 500 to 50,000,
Those having a molecular weight of ~ 40000 are more preferred.

In the block copolymer used as an antistatic agent for a polycarbonate resin of the present invention, a polyoxy 1,2-alkylene ether-1,2-alkylene carbonate block (hereinafter simply referred to as a polyether carbonate block) is represented by the following formula (1). It is composed of one or more of the units shown. Examples of such polyether carbonate blocks include 1) polyoxyethylene ether ethylene carbonate block, 2) polyoxy 1,2-propylene ether-1,2-propylene carbonate block, and polyoxy-1,2-n-butylene ether-1,2. -N-butylene carbonate block, polyoxy-1,2-isobutylene ether-
There are 1,2-isobutylene carbonate block, polyoxyphenylethylene ether phenylethylene carbonate block, polyoxy-1,2-cyclohexene ether-1,2-cyclohexene carbonate block and the like. Among them, a polyoxyethylene ether ethylene carbonate block is preferred.

The block copolymer used as the antistatic agent for the polycarbonate resin of the present invention is a polyoxyalkylene block / polyether carbonate block = 1.
It has a ratio of 0/90 to 90/10 (weight ratio) and a number average molecular weight (polystyrene molecular weight conversion value measured by the GPC method) of 5,000 to 100,000. When the proportion of the polyoxyalkylene block is higher than the above, the compatibility or dispersibility of such a block copolymer and the polycarbonate resin is deteriorated, and the physical properties of the polycarbonate resin, especially the transparency, are impaired. When the proportion of the polyoxyalkylene block is lower than the above, the antistatic effect obtained by such a block copolymer decreases.

The block copolymer used as the antistatic agent for the polycarbonate resin of the present invention is prepared by adding a polyether (poly) ol having 1 to 6 hydroxyl groups and a polyoxyalkylene block in the molecule to a polyether (poly) ol in the presence of a catalyst. , 2-alkylene carbonate obtained by ring-opening polymerization. Such polyether (poly) ols include polyether monols having one hydroxyl group in the molecule, 2-ethers in the molecule.
There are polyether polyols having six hydroxyl groups.
The polyether monool or polyether polyol used as a raw material is obtained by adding an alkylene oxide, specifically, ethylene oxide, propylene oxide, or 1,2-butylene oxide to an active hydrogen compound, alone or in a mixture. Examples of the polyether monool include an alkylene oxide adduct of a monohydric alcohol or a monohydric phenol, and examples of the polyether polyol include an alkylene oxide adduct of a divalent to hexavalent polyhydric alcohol and an alkylene oxide adduct of a dihydric phenol. Can be advantageously used. Examples of the catalyst used for the ring-opening polymerization of 1,2-alkylene carbonate include known catalysts, for example, those having at least two alkoxy groups in the molecule, the second of the periodic table.
Organometallic complexes consisting of metals of Groups 4 to 4 can be advantageously used.

When a 1,2-alkylene carbonate is reacted with a hydroxyl group of a polyether monool or a polyether polyol in the presence of a catalyst, usually, 2 mol of 1,2-alkylene is obtained.
One mole of carbon dioxide is released from the alkylene carbonate to give oxy-1,2-alkylene ether-1,2.
-An alkylene carbonate group is formed,
A ring-opening reaction and a ring-opening elimination reaction of the alkylene carbonate occur alternately to form a polyoxy 1,2-alkylene ether-1,2-alkylene carbonate block, that is, a polyether carbonate block.

The terminal of the polyether carbonate block obtained by the above reaction usually becomes a hydroxyl group. In the present invention, such a terminal can be modified with an acyl group, an alkyl group or a silyl group. Specifically, 1) an acylating agent such as an organic monocarboxylic anhydride or an organic monocarboxylic acid halide is reacted with a terminal hydroxyl group to give an acylated terminal; and 2) an alkylating agent such as an alkyl halide is added to the terminal hydroxyl group. And 3) a silyl etherating agent such as trialkylchlorosilane, trialkylhydrogensilane, or trialkylsilanol is reacted with the terminal hydroxyl group to form a silyl ether terminal. When the terminal-modified product is melt-kneaded with a polycarbonate resin, undesirable reactions such as transesterification and depolymerization of the polycarbonate resin can be reduced.

The polycarbonate resin composition of the present invention comprises:
The antistatic agent for a polycarbonate resin as described above is contained in an amount of 1 to 30 parts by weight, preferably 5 to 25 parts by weight, based on 100 parts by weight of the polycarbonate resin. When the content of the antistatic agent for the polycarbonate resin is less than 1 part by weight, the antistatic property is insufficient, and when it exceeds 30 parts by weight, the softening point temperature of the polycarbonate resin composition is lowered or the physical properties are deteriorated. Become. In particular, a polyoxyalkylene block / polyether carbonate block composed of polyoxyethylene blocks / 30 / 70-60 / 40 (weight ratio) in a block copolymer used as an antistatic agent for the polycarbonate resin, based on 100 parts by weight of the polycarbonate resin. The copolymer containing 5 to 25 parts by weight of the block copolymer having the above ratio has excellent antistatic properties while maintaining the physical properties inherent to the polycarbonate resin, particularly transparency.

When incorporating the antistatic agent for a polycarbonate resin of the present invention into a polycarbonate resin, both are melt-kneaded at a temperature not lower than the melting point of the polycarbonate resin. In this case, the polycarbonate resin in the molten state may be directly kneaded with the antistatic agent for polycarbonate resin, or a master chip may be prepared in advance and then kneaded. (Compatibility or dispersibility).

In the polycarbonate resin composition of the present invention, the polycarbonate resin used is bisphenol A
It has a basic skeleton of a polycarbonate synthesized by a condensation reaction of phenol with phosgene or diphenyl carbonate, but may be partially modified with bisphenol S, tetrabromobisphenol A, or the like. Further, the polycarbonate resin composition of the present invention can contain polystyrene, acrylonitrile-styrene copolymer, polyphenylene ether resin and the like in a range of 50% by weight or less based on the polycarbonate resin. Further, the polycarbonate resin composition of the present invention may contain stabilizers such as antioxidants and ultraviolet absorbers in addition to various fillers, reinforcing fibers and pigments.

[0018]

EXAMPLES Test Category 1 (Synthesis of Block Copolymer Used as Antistatic Agent for Polycarbonate Resin) A block copolymer used as an antistatic agent for polycarbonate resin was synthesized, and the number average molecular weight and polystyrene of the block copolymer were measured. Table 1 summarizes the ratio of the oxyalkylene block / polyether carbonate block (weight ratio). These were measured as follows.

Number average molecular weight: expressed by polystyrene equivalent number average molecular weight measured by gel permeation chromatography. Ratio of polyoxyalkylene block / polyether carbonate block (weight ratio): Calculated from ¹ H-NMR proton ratio. In Table 1, it is indicated by A / B.

Example 1 A flask was charged with 50 parts of polyethylene glycol having a number average molecular weight of 20,000 (parts by weight, the same applies hereinafter), and the flask was purged with nitrogen.
Parts were added. Heat to 200-210 ° C with stirring,
50 parts of ethylene carbonate were added dropwise over 2 hours.
After aging at this temperature for 4 hours, the mixture was cooled to room temperature to obtain 87.5 parts of a white block copolymer. This block copolymer was discharged onto a drum breaker to form flakes.

Example 2 In the same manner as in Example 1, using 30 parts of methoxypolyethylene glycol having a number average molecular weight of 20,000 at one end, 70 parts of ethylene carbonate and 0.1 part of sodium pentaethoxy metastannate as a catalyst, a white 82 parts of a block copolymer was obtained and flaked.

Example 3 In the same manner as in Example 1, 50 parts of polyethylene glycol having a number average molecular weight of 6000 and 50 parts of ethylene carbonate
Part, 50 parts of 1,2-propylene carbonate and 0.1 part of sodium borohydride as a catalyst, 126 parts of a white block copolymer was obtained and flaked.

Example 4 In the same manner as in Example 1, 10 parts of polyethoxylated diglycerin having a number average molecular weight of 2000, 90 parts of ethylene carbonate, and sodium borohydride 0.1 part as a catalyst.
Using 1 part, 78 parts of a white block copolymer was obtained and flaked.

Example 5 In the same manner as in Example 1, 80 parts of polyethoxylated trimethylolpropane having a number average molecular weight of 5000, 20 parts of ethylene carbonate, and 0.1 part of sodium pentaethoxy metastannate as a catalyst were used. Was obtained and flaked.

Example 6 100 parts of the block copolymer synthesized in Example 1 was charged into a flask, and after purging with nitrogen, 120 to 1 were stirred.
The mixture was heated to 30 ° C., and 0.7 parts of acetic anhydride was added dropwise. After completion of the dropwise addition, the mixture was aged for 2 hours, and acetic acid produced as a by-product was removed from the system under reduced pressure to obtain a terminal-modified block copolymer. This was flaked in the same manner as in Example 1.

Example 7 100 parts of the block copolymer synthesized in Example 4 was charged into a flask, and after substituting with nitrogen, 120 to 1 with stirring.
The mixture was heated to 30 ° C., and 3.5 parts of trimethylmethoxysilane was added dropwise. After completion of the dropwise addition, the mixture was aged for 2 hours, and methanol produced as a by-product was removed from the system under reduced pressure to obtain a terminal-modified block copolymer. This was flaked in the same manner as in Example 1.

[0027]

[Table 1]

Test Category 2 (Preparation of Polycarbonate Resin Composition and Evaluation of Molded Product Obtained Using It) Test Category 1 was applied to 100 parts by weight of polycarbonate resin.
The block copolymer synthesized in the above was blended as shown in Table 2. This was melt-kneaded at a resin temperature of 280 ° C. using a vented 40 mmφ extruder, extruded, and pelletized. Next, the pellets were molded by an injection molding machine at a cylinder temperature of 230 ° C. and a mold temperature of 60 ° C. The physical properties of the molded product were measured as follows, and the state was evaluated. The results are shown in Tables 3 and 4.

Tensile strength: ASTM D638 Flexural strength, flexural modulus: ASTM D790 Izod impact strength: ASTM D256-56A.

Surface specific resistance: 2 mmt × 80 mmφ
, And cut out into a test piece for measurement. After treating this test piece under the following conditions 1 or 2, 23 ° C. × 5
In an atmosphere of 0% RH, surface resistivity was measured using a super insulation resistance meter SM-8210 manufactured by Toa Denpa Kogyo. Condition 1: The test piece was conditioned at 23 ° C. × 50% RH for 24 hours and then measured. Condition 2: the test piece was washed with a 1% aqueous solution of a detergent (Mama Lemon, manufactured by Lion Oil & Fat Co., Ltd.), and then the detergent was thoroughly rinsed with distilled water to remove water on the surface.
The measurement was performed after adjusting the humidity at × 50% RH for 24 hours.

Appearance, transparency and delamination of the molded article: The molded article or its fracture surface was visually observed and evaluated according to the following criteria. Appearance; ○: homogenous throughout △: inhomogeneous part recognized ×: many inhomogeneous parts Transparency; ○: completely transparent or almost completely transparent △・ Semi-transparent × ・ ・ ・ Completely opaque Laminar peeling; ○ ・ ・ ・ No laminar peeling is observed △ ・ ・ ・ Some laminar peeling is observed × ・ ・ ・ Laminar peeling is remarkable

[0032]

[Table 2]

In Table 2, * 1: sodium dodecylbenzenesulfonate * 2: polyethylene glycol having a number average molecular weight of 150,000 * 3: styrene-acrylonitrile copolymer (trade name: Estyrene AS-20 manufactured by Nippon Steel Chemical Co., Ltd.) * 4: Polystyrene (trade name Estyrene GP-20 manufactured by Nippon Steel Chemical Co., Ltd.)

[0034]

[Table 3]

[0035]

[Table 4]

[0036]

As is apparent from the above, the present invention described above has an effect that excellent antistatic properties can be imparted without impairing the physical properties inherent to polycarbonate resins, particularly transparency.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 64/18 CA (STN) REGISTRY (STN)

Claims (3)

(57) [Claims] 1. A compound having 1 to 6 hydroxyl groups and 2 to 2 carbon atoms in a molecule.
A block copolymer obtained by ring-opening polymerization of a 1,2-alkylene carbonate with a polyether (poly) ol having a polyoxyalkylene block composed of 4 oxyalkylene units and a polyoxyalkylene block / Polyoxy 1,2-alkylene ether-
1,2-alkylene carbonate block = 10/90
Number average molecular weight of 5 to 90/10 (weight ratio)
An antistatic agent for a polycarbonate resin, comprising a block copolymer of 000 to 100,000. A:
Polyoxy 1,2-alkylene ether-1,2- composed of one or more units represented by the following formula 1:
Alkylene carbonate block [Formula 1] [In the formula 1, X ¹ and X ² : an ethylene group or an ethylene group simultaneously substituted with the same or different hydrocarbon group having 1 to 6 carbon atoms] 2. The antistatic agent for a polycarbonate resin according to claim 1, wherein the terminal of the polyoxy 1,2-alkylene ether-1,2-alkylene carbonate block of A is modified with an acyl group, an alkyl group or a silyl group. 3. A polycarbonate resin composition comprising 1 to 30 parts by weight of the antistatic agent for a polycarbonate resin according to claim 1 or 2 based on 100 parts by weight of the polycarbonate resin.