JPH02311554A - Polyester resin composition - Google Patents

Abstract

PURPOSE:To prepare a resin compsn. which crystallizes rapidly and can provide a molded article excellent in the dimensional stability, mechanical properties, and heat resistance at a high productivity by compounding an arom. polyester resin with a specific high mol.wt. paraffin. CONSTITUTION:100 pts.wt. arom. polyester resin (pref. mainly comprising a polyethylene terephthalate resin) is compounded with 0.05 to 10 pts.wt. 40 to 100C paraffin or its oxygen-contg. deriv. [45 to 95C paraffin (wax) is pref.; and the pref. oxygen-contg. deriv. has the basic structure of said paraffin and contains oxygen as COOH, OH, or CO]. The addition of said paraffin or said deriv. results in a compsn. which crystallizes relatively rapidly. The resulting compsn., being easily introduced into a molding machine, can provide a molded article excellent in the dimensional stability, mechanical properties, and heat resistance in a short cycle time.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a resin composition containing an aromatic polyester resin as a main resin component. More specifically, the present invention relates to a resin composition in which molding productivity is significantly improved by blending a specific polymeric paraffin into an aromatic polyester resin.

(Prior art) Conventionally, aromatic polyester resins, mainly composed of polyethylene terephthalate resin, have excellent mechanical properties, heat resistance, chemical resistance, dimensional stability, etc., and are used not only for fibers but also for
Widely used as film and engineering resin. A particular problem with the use of aromatic polyester resins as molding materials is that they have a relatively slow crystallization rate under molding conditions compared to other resins. The crystallization rate directly affects the productivity of molded products, that is, the molding cycle.

Many nucleating agents have been developed to increase the crystallization rate and degree of crystallinity of aromatic polyester resins. For example 5
Inorganic substances with microscopic particles of less than μ, i.e., metal oxides,
Alkaline earth metal salts, metal powders, talc powders, glass powders, and the like are known (see, for example, Japanese Patent Publications No. 44-7542 and No. 44-15192). Examples of organic substances include aliphatic carboxylic acids and aromatic carboxylic acids having 2 to 33 carbon atoms, such as stearic acid, lauric acid, linoleic acid, oleic acid, arachic acid, carnaubic acid, lignoceric acid, cerotic acid, petroselic acid, Metal salts of organic carboxylic acids such as polymeric carboxylic acids such as behenic acid, erucic acid, montanic acid, benzoic acid, terephthalic acid or ionomers are known (for example,
No. 29977, No. 47-14502, No. 47-324
No. 35 and No. 48-4098).

Some of these nucleating agents cause a decrease in the molecular weight of the aromatic polyester resin, and some of these nucleating agents do not have a sufficient effect of increasing the crystallization rate.

(Objective of the Invention) Therefore, an object of the present invention is to provide an aromatic polyester resin composition having a relatively fast crystallization rate.

Another object of the present invention is to provide an aromatic polyester resin composition that has excellent dimensional stability, mechanical properties, heat resistance, and biting properties, and has a short molding cycle, that is, has high productivity of molded products. be.

Yet another object of the present invention is to provide an aromatic polyester resin composition that exhibits relatively little reduction in molecular weight compared to resins without added nucleating agents.

Yet another object of the present invention is to provide an economically advantageous aromatic polyester resin composition using a nucleating agent that is readily available and relatively inexpensive.

Still another object of the present invention is to provide a molded product with less occurrence of paris and less surface adhesion of whitening substances, and furthermore, to provide a molded product with excellent appearance without coloring based on a nucleating agent. An object of the present invention is to provide a polyester resin composition.

Yet another object of the present invention is to provide a glass fiber reinforced aromatic polyester resin composition that provides excellent physical properties and stability.

Further objects of the invention will become apparent from the description below.

(Structure of the Invention) According to the research of the present inventor, the objects and advantages of the present invention are as follows: (1) (a) Aromatic polyester resin (component A) 1
(2) (a) an aromatic polyester resin composition consisting of 0.00 parts by weight and (b) 0.05 to 10 parts by weight of paraffin having an average carbon number of 40 to 100 or its oxygen-containing derivative (component B);
100 parts by weight of aromatic polyester resin (component A), (b) 0.05 to 10 parts by weight of paraffin having an average carbon number of 40 to 100 or its oxygen-containing derivative (component B), and (c) reinforcing filler (component C) an aromatic polyester resin composition consisting of 5 to 200 parts by weight, and (3)
(a) 100 parts by weight of aromatic polyester resin (component A), (b) 0.05 to 10 parts by weight of paraffin having an average carbon number of 40 to 100 or its oxygen-containing derivative (component B), (c) reinforcing filler ( It has been found that this can be achieved by an aromatic polyester resin composition comprising 5 to 200 parts by weight of component C) and 0.05 to 5 parts by weight of (d) an epoxy compound (component D).

According to the present invention, the nucleating agent has an average carbon number of 40
By using ~100 paraffin or its oxygen-containing derivative (component B), the biting property of aromatic polyester resin in the injection molding machine is improved, and the crystallization rate becomes extremely fast, making it easier to mold from the molding machine. The removal time of the product is shortened, the molecular weight loss of the obtained molded product is extremely small, and the molded product has a good appearance without surface whitening and has excellent physical properties.

Aromatic polyester resin compositions using montan wax salts or montan wax ester salts, which are relatively high-molecular paraffins, as nucleating agents have been known (for example, see Japanese Patent Publication No. 46150/1983). However, the resin composition of the present invention has a higher crystallization rate than when using montan wax or the like.

The nucleating agent (component B) blended into the resin composition of the present invention is paraffin (wax) having an average carbon number of 40 to 100 or an oxygen-containing derivative thereof. This paraffin (wax) preferably has an average carbon number in the range of 45 to 95. This long-chain paraffin or its oxygen-containing derivative is usually a mixture having the above-mentioned average carbon number, and has an average molecular weight of about 560 to about 1,400, preferably about 63
It ranges from 0 to about 1330.

The oxygen-containing derivative of paraffin has the paraffin as a basic skeleton, and oxygen has a carboxyl group,
It means a derivative containing a hydroxyl group, a carbonyl group, an aldehyde group, an ester bond, etc., and these groups or bonds may be formed during the manufacturing process of paraffin. It may be formed by partial oxidation. Further, the oxygen-containing derivative of paraffin may be a metal salt, and the metals forming the salt include metals from main groups 1 to 3 of the periodic table, such as alkali metals such as lithium, potassium, and sodium: Examples include alkaline earth metals such as magnesium, calcium, and barium; and zinc; among these, sodium, calcium, magnesium, and zinc are preferred.

The paraffin or its oxygen-containing derivative (component B) preferably has a freezing point in the range of 85°C to 120°C, more preferably in the range of 88°C to 115°C.

In addition, in the case of oxygen-containing derivatives, acid value (AV, mgKOH/
It is advantageous that g) is 110 or less, preferably 40 or less, and it is further advantageous that the saponification number (mgKOH/g) is 180 or less, preferably 110 or less.

Component B as a nucleating agent of the present invention can be used regardless of its manufacturing method as long as it has the above-mentioned properties. However, long-chain paraffins such as component B hardly exist in nature, and are usually obtained as synthetic wax when producing synthetic petroleum from coal in the Fischer-Tropsch process.

The only company currently implementing the Fischer-Tropsch method on a commercial scale is South Africa's SAS.
OL, Ltd) only, and from this Sasol company,
A product commercially available as Sasol Wax (■) can be used as component B of the present invention. Specifically, straight type Hl, H2, C1 or C2 of Sasol wax [F] commercially available from Sasol Co., Ltd.
High melting point paraffin wax called Al, oxidized type called A6 or A7, A2, A3 or A14
(Some fatty acids form metal salts) can be used as component B of the present invention. The straight type above has a density of 0.94~
0.96 g/cm'' is preferred, and this type is a substantially linear paraffin.The characteristics of each of these types will be summarized below.

Physical Properties of Various Types of Sasol Wax■ All of the waxes commercially available from Sasol Co., Ltd. mentioned above meet the conditions as component B of the present invention, and can be used as is or in combination of two or more. I can do it. Further, these waxes may be partially modified as long as they satisfy the requirements as component B of the present invention. For example, partially oxidized products, esterified products, metal salts (
For example, sodium salt, calcium salt, magnesium salt,
Zinc salts, etc.). These esterification and metal chlorination may be carried out partially or completely.

On the other hand, among the above-mentioned waxes, oxidized type (AI).

When one or more types of 86 or A7) 8 and oxidation oxidation type (A2, A3 or Al4) are left in a molten state, esterification and gelation reactions occur relatively easily.
Waxes with increased viscosity and, in some cases, high hardness are formed, but these heat-treated waxes can also be used as component B of the present invention.

In addition, to create a metal salt of the wax, the oxidized or oxidized saponified wax is easily saponified with a common alkali such as potassium carbonate, sodium carbonate, potassium hydroxide, or sodium hydroxide. Carboxylate or ester salts can be formed.

In the present invention, component B is an aromatic polyester resin (
A component) 0.05 to 10 parts by weight per 100 parts by weight,
It is preferably blended in a proportion of 0.1 to 5 parts by weight. In addition to the component B, the resin composition of the present invention also contains conventionally known inorganic or organic carboxylic acid salts as nucleating agents, metal salts of polymeric carboxylic acids such as ionomers (for example, Japanese Patent Application Laid-open No. 158452/1983, Special Public Service No. 45-26225
montanic acid wax salts (for example, Japanese Patent Publications No. 47-13137, No. 58-46150, No. 58)
-46151, 62-49310, 62-51
No. 300, JP-A-59-159848, JP-A No. 60-15
5093), acetylacetone alkali metal chelate (for example, see Japanese Patent Publication No. 62-61066)
By using these in combination, the effect can be further enhanced.

Component A forming the resin composition of the present invention is an aromatic polyester resin, and this aromatic polyester resin is a polyester whose main dicarboxylic acid is an aromatic dicarboxylic acid. Specific examples of this aromatic dicarboxylic acid include:
Terephthalic acid, isophthalic acid, naphthalene (2,6- or 2,7-) dicarboxylic acid, (4,4'- or 3.
4'-) diphenyl dicarboxylic acid, (4,4'- or 3,4'-) diphenyl ether dicarboxylic acid, (4,
4'- or 3.4'-) diphenylsulfone dicarboxylic acid, (4,4'4 or 3.4'-) diphenoxyethane dicarboxylic acid, among which terephthalic acid, 2,6-naphthalene dicarboxylic acid Acids are preferred.

On the other hand, specific examples of diols that form polyesters together with the aromatic dicarboxylic acids include ethylene glycol,
Trimethylene glycol, propylene glycol, tetramethylene glycol, neopentylene gelicol, hexamethylene glycol, cyclohexane dimetatool, tricyclodecane dimetatool, 2.2-bis(4.
Examples include β-hydroethoxydiphenyl)propane, 4,4'-bis(hydroxyethoxy)diphenylsulfone, diethylene glycol, and ethylene glycol, tetramethylene glycol or l.

4-Cyclohexane dimetatool is preferred.

Further, the aromatic polyester may be one in which 15 mol% or less of the aromatic dicarboxylic acid is replaced with an oxyacid or aliphatic dicarboxylic acid such as p-oxybenzoic acid, succinic acid, adipic acid, or sebacic acid. Often, a small proportion of a monofunctional or polyfunctional compound such as benzoic acid, pentaerythritol, trimethylolpropane, trimellitic acid, or pyromellitic acid may be added.

Particularly preferred aromatic polyesters as component A are:
Polyethylene terephthalate, polybutylene terephthalate, polyethylene-2,6-naphthalate and a copolymerized polyester containing at least 70 mol%, preferably at least 80 mol%, of ethylene terephthalate units, butylene terephthalate units or ethylene-2°6-naphthalate units, or It is a block copolymerized polyester.

The degree of polymerization of the aromatic polyester is generally sufficient as long as it can be used as a molding material, and is 0.4 expressed in terms of intrinsic viscosity.
-1.2, preferably 0.5-1.0 is common. This intrinsic viscosity is a value measured in 0-chlorophenol solvent at a temperature of 35°C.

In the case of the reinforced aromatic polyester resin composition of the present invention, the reinforcing filler (component C) is not particularly limited as long as it is commonly used for the purpose of reinforcing resin molded products. As component C, fibrous or granular inorganic or organic substances are generally used. Examples of the fibrous reinforcing filler include glass fiber, shirasu glass fiber, alumina fiber, silicon carbide fiber, ceramic fiber, gypsum fiber, stainless steel fiber, carbon fiber, and wholly aromatic polyamide fiber.

On the other hand, granular reinforcing fillers include silicates such as wollastonite, sericite, kaolin, mica, clay, silica, bentonite, asbestos, tar, and aluminosilicate; alumina, silicon oxide, magnesium oxide, zirconium oxide, Metal oxides such as titanium oxide; carbonates such as calcium carbonate, magnesium carbonate, and dolomite; sulfates such as calcium sulfate and barium sulfate; and glass peas, glass peaks, boron nitride, silicon nitride, potassium titanate, etc. can be mentioned.

These fillers may be subjected to surface treatment, for example, coupling treatment (silane, titanate, etc.), if necessary. Furthermore, glass fibers surface-treated with a polyfunctional epoxy compound as described in Japanese Patent Publication No. 58-25378 can also be used.

The blending ratio of the reinforcing filler (CF!r, min) mentioned above is A
The amount is from 5 to 200 parts by weight, preferably from 10 to 150 parts by weight, per 100 parts by weight of the components. The blending ratio of reinforcing filler is 5
If it is less than 200 parts by weight, there is no point in adding it, while if it exceeds 200 parts by weight, not only will molding become difficult, but the physical properties of the molded product will also be unsatisfactory.

In the present invention, the epoxy compound (component D) is a compound having at least one epoxy group in the molecule, and examples include bisphenol A type, novolac resin type, aromatic carboxylic acid type, and alicyclic compound type.

Among these, suitable polyfunctional epoxides include alkylene polyol glycide ether and butanediol.
(1,4) diglyside ether or bisphenol A
It is a bisphenol A-type epoxy compound obtained by reacting chlorohydrin with epichlorohydrin.

In injection molding, molded products with sufficient mechanical properties can generally be obtained without the addition of epoxide. However, when a molded product is obtained by injecting into a mold, particles are likely to occur along the particle line of the mold. In order to prevent this, it is possible to obtain a product with less occurrence of flaking by using a polyester with a high melt viscosity, and also by using 0.05 to 0.5 parts by weight of an epoxy compound (component D). It is possible to prevent the occurrence of Paris. In addition, the addition of an epoxy compound can also be expected to have the effect of reducing the adhesion of whitening substances to the surface of finished products.

In addition to the above-mentioned components A, B, C, and D, the resin composition of the present invention may contain other components that are commonly used as additives for resins within a range that does not impair the purpose of the present invention. be able to. Other ingredients that may be blended include, for example, stabilizers such as phosphoric acid esters and phosphorous acid esters;
Antioxidants such as hindered phenols; flame retardants such as red phosphorus, triphenyl phosphate, phosphonic amides, brominated biphenyl ethers, nuclear brominated bisphenol A epoxides, nuclear brominated polycarbonates; antimony trioxide, boric acid Flame retardant aids such as zinc; other materials include ultraviolet absorbers, antistatic agents, pigments, and blowing agents.

Furthermore, the resin composition of the present invention may contain other resins in an amount of 20% by weight or less, preferably 10% by weight or less based on component A, as long as this does not impair the purpose of the present invention. Examples of such resins include tlf
Polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-4-methylpentene-I copolymer, globylene-butene-I copolymer, polystyrene, A
BS, polyacrylic acid, polymethyl acrylate, ethylene-acrylic acid copolymer, polyvinyl acetate, ethylene-
Vinyl acetate copolymer, polyfluoroethylene, polyester elastomer, polycaprolactam, polyhexamethylene adipamide, poly-rho-7 dilene iso-7 thalamide, polycarbonate, polyphenylene ether, phenolic resin, melamine resin, epoxy resin, unsaturated polyester Examples include thermoplastic resins or thermosetting resins such as resins.

The resin composition of the present invention can be produced by blending component A and component B, optionally component C, component D, or the above-mentioned additional components if desired. The method and conditions for blending these components are preferably such that the components can be mixed uniformly with each other. A desirable method is under conditions where component A and component B can be uniformly melted and kneaded,
This is a method to obtain a homogeneous mixture by mixing using a blender, niegu, roll, extruder, etc. Furthermore, the obtained mixed composition can be kneaded with an extruder, extruded into a wire shape, and cut into appropriate lengths to form chips.

It is also possible to use component B by sprinkling it on a chip-shaped resin made of other components (triblend).

The thus obtained resin composition of the present invention can be made into a molded article by a method such as injection molding, extrusion molding, compression molding, or rotational molding. In the case of injection molding, there is no need to particularly heat the mold used, but it is generally heated between 50°C and 16°C.
When molded in a mold maintained at a temperature of 0°C, preferably 70°C to 150°C, the crystallization rate is further accelerated, the time taken to remove the molded product from the mold is shortened, and the molded product is uniformly crystallized. This is preferable because a molded article with a high quality can be obtained.

Thus, according to the present invention, instead of known nucleating and deafening agents, such as metal salts of polymeric carboxylic acids such as ionomers and montanic acid waxes (salts, esters or ester salts thereof), B of the present invention can be used. Ingredients (average carbon number 40
By using paraffin or its oxygen-containing derivative of 100 to 100%, it exhibits an excellent crystallization promoting effect compared to these known nucleating agents, and molded articles suitable for the purpose of use can be obtained.

For example, examples of application and use of Montanic acid wax (its salt, ester, or ester salt) as a known nucleating agent will be shown below. ingredients are used.

A: Example of applying a nucleating agent to injection molding of polyester resin: For example, Japanese Patent Publication Nos. 58-46150 and 58-46151
No. 62-49310, No. 62-51300, No. 62-61066, JP-A No. 59-109551, No. 59-159848, No. 60-47058.

The inventions described in these publications use a nucleating agent to (i) accelerate crystallization rate, improve mold releasability, (■) improve bitability during molding, and whiten the surface of molded products. (■) Improve the tensile strength, heat resistance, hydrolysis resistance, and dimensional stability of molded products. Furthermore, by using an epoxy compound or an ether compound such as a specific polyalkylene oxide (1v) Suppresses the occurrence of whitening and reduces the adhesion of whitening substances on the surface of products.

(v) Even when molded at a low mold temperature (70 to 110°C), it is possible to obtain a molded product with excellent mold releasability and heat resistance, as well as excellent biting properties. On the other hand, in JP-A-54-139654 and JP-A-158452, butyl calpitol is used to obtain a molded product with good surface properties and high gloss when reinforced or filled PET is molded at a low molding temperature (below 110°C). Adipate. It has been proposed to use external plasticizers such as triethylene glycol caprate-caprylate, dibenzoates of dipropylene glycol or neopentyl glycol, and benzophenone. Even in these proposals, it is essential to use a nucleating agent such as a sodium salt of an ethylene/methacrylic acid copolymer.

B: Example of applying a nucleating agent to extrusion molding of polyester resin: (1) Manufacture of extruded foam products (e.g. Japanese Patent Publication No. 57-464
(Refer to Publication No. 57) It is characterized by the use of a nucleating agent in addition to a jepoxy compound during melt extrusion molding of polyester to stably obtain a foam molded product having an excellent appearance and uniform fine bubbles.

(2) Manufacture of transparent and slippery polyethylene terephthalate film (see, for example, Japanese Patent Publication No. 62-56906) It is said that by using a nucleating agent, surface smoothness can be maintained and a transparent and slippery film can be obtained. .

(3) Manufacture of open-pull trays for food (see Takashi Uemura, Plastics Vol. 37, No. 9, pp. 26-30) In the process of manufacturing low-crystalline sheets, nucleating agents such as inorganic salts and organic salts are It has been shown that by pre-blending the agent, it is possible to promote crystallization and impart heat resistance in the next step of molding the tray, and it is also possible to improve the molding cycle.

C: Manufacture of polyester containers by stretch blow molding (for example, see Japanese Patent Application Laid-Open No. 57-12524 '6) By blending a nucleating agent in advance in the process of manufacturing the preform, it A transparent tableware container (for example, a bottle) with excellent heat shrinkage resistance and good appearance can be obtained.

In the proposals for adding a nucleating agent to many polyester resins as mentioned above, by using component B of the present invention as a nucleating agent, a more excellent effect can be achieved compared to these proposals, and it is suitable for the purpose and use. molded products can be easily obtained.

In particular, it is extremely preferable to use a resin composition using the wax manufactured by Sasol Co., Ltd., particularly H2 wax, as component B of the present invention for open-pull trays for food products and containers for food products. The reason is that H2 wax does not contain antioxidants and is approved by the Food and Drug Administration (FDA).
This is because it has been approved for use and is safe as an additive for food broadcasting products.

The resin composition containing component B in the present invention has different molding methods, molded product sizes, Although it is not constant depending on the molding conditions, for example, in injection molding, under suitable conditions, the injection molding cycle is actually shortened by 5 to 15 seconds. This reduction in cycle time may seem trivial, but considering that injection molding cycles are typically 10 to 40 seconds, its economic value is extremely large.

The present invention and its effects will be explained below with reference to Examples and Comparative Examples. These examples are mainly experiments using injection molding, but since the mechanism that produces these effects is mainly based on nucleation and crystallization promotion, other molding methods (
It goes without saying that similar effects can be expected even with extrusion molding, blow molding, etc.).

In addition, polyethylene terephthalate (hereinafter abbreviated as "PET") used in the following examples and comparative examples is a mixture of phenol and tetrachloroethane:
The intrinsic viscosity measured at 25°C in a mixed solvent of 1 weight ratio is 0.
．． It was from 68.

Examples 1 to 3 and Comparative Examples 1 to 4 (comparative measurement by DSC): Additives shown in Tables 1-(1) and 1-(2) below were added to PET. They were each heated to 300° C. and melted.

Next, the molten mixture was rapidly cooled with liquid nitrogen to prepare an amorphous sample piece for DSC measurement.

Each sample piece was measured using a differential calorimeter (DSC-30 manufactured by Shimadzu Corporation).
system), the temperature was raised at a heating rate of 10°C/min, and the temperature at which crystallization started, the temperature at which the exothermic reaction reached its maximum, and the temperature at which crystallization ended were measured. We investigated the effects. The results are shown in Tables 1-(1) and 1-(2) below.

Table 1-(1) Comparative measurement by Dsc As shown in the table above, known sodium montanate salts have a low crystallization initiation temperature, and nucleation starts at a low temperature, but the nucleation rate and crystallization rate are lower than that of Sasol AI. , was found to be slower than its sodium salt, and its maximum temperature and final temperature were not significantly different from those of the blank. On the other hand, when Sasol Al and its sodium salt were added, both the nucleation rate and the crystallization rate were significantly faster than when no additive was added.

Table-1-(2) Comparative measurement by DSC (talc added)
As can be seen from the above table, even when talc, which is an inorganic salt nucleating agent, is used in combination, Sasol Al sodium salt is more effective than montanate.

Example 4.5 and Comparative Example 5.6 (Comparative measurement using DSC) 70 parts by weight of PET, 2 parts by weight of an inorganic salt nucleating agent talc, and 30 parts by weight of glass fiber (C5-3J-941SP manufactured by Nittobo Co., Ltd.) was used as a reinforcing filler.

The additives shown in Table 2 were added to this in the proportions shown in the same table, and the mixture was melt-kneaded at 260°C using an extruder [KCK80X2-35VEX (5) - output rate: approximately 6 kg/ha) to form pellets. Obtained. The obtained pellets were dried with hot air at 140°C for 15 hours and then heated and melted at 300°C.

Next, the molten mixture was rapidly cooled using liquid nitrogen to prepare a sample piece for DSC measurement. A scale for comparing and measuring the nucleation ability of the additive used and its crystallization rate by measuring the crystallization start temperature, maximum temperature, and end temperature of each sample piece under the same conditions as in the previous example. And so.

Table 2 Comparative measurement by DSC (when reinforced with glass fiber) In the above table, Ac1yn 272A and 285A are made of low molecular weight ethylene/acrylic acid copolymer manufactured by Allied Signal Co., Ltd., partially or completely with sodium ions. It is a neutralized low molecular weight ionomer.

According to the company's catalog, it is said to be used as a crystallization nucleating agent that is more effective and effective than LDPE, LLDPE, Sur I yn, etc. as a crystallization accelerator for PET resin.
Especially the sodium type Ac1yn 272A, 2
85A is considered to be highly effective. However, from the above table, it can be seen that Sasol At sodium salt and Sasol Hel sodium salt combined with ammonium humate are crystallization nucleating agents with a much lower crystallization initiation temperature and a higher nucleation effect.

70 parts by weight of PET, 30 parts by weight of glass fiber (C5-3J-941SP manufactured by Nittobo Co., Ltd.) as a reinforcing filler, and 2 parts by weight of talc.
parts by weight were added, and the mixture was further triblended in the proportions shown in Tables 3 and 4, using an extruder (KcK80x2-35
vEx(5)) at a discharge rate of approximately 6 kg/hr at 260° C. to obtain pellets.

The pellets were dried in a hot air dryer at 140° C. for 5 hours and subjected to a test for evaluation of injection moldability.

For evaluation of injection moldability, an injection molding machine (Japan Steel Works N40B) was used.
I[) was used. Cylinder a degree 260°C1 resin injection pressure 520 kg/cm”G and mold temperature 130°
Tested under conditions C. The mold is 127mm long
A rectangular mold with a width of 12.7 mm and a thickness of 3.2 mm was used.

In addition to observing the appearance of the molded product, the test was evaluated by measuring the injection moldability described below.

(1) Metering time: To avoid short shots due to pellets fed from the hopper during molding not getting bit into the screw of the injection molding machine and resulting in unstable metering, the rotational speed is varied within the range of 22 Orpm” to 1100 rpm to ensure stable metering. The weighing time (seconds) when the pellets could be weighed was measured and used as a measure for evaluating the biting ability of the pellets.

(2) Injection time: Evaluation was made by measuring the holding pressure time (injection time) at which sink marks and pinholes no longer occur.

(3) Cooling time: The mold release time is measured by changing the cooling and solidifying time in the mold, opening the mold, and automatically releasing the mold without any molded pieces sticking to the mold - the cooling time (seconds) And so. Furthermore, the nucleating ability and crystallization promoting effect of various nucleating agents were evaluated based on the total injection time and cooling time.

In the case of insufficient crystallization and solidification - For example, when molding only PET and glass fiber, the injection time is 7 seconds, but due to insufficient crystallization and solidification, the molded pieces adhere to the mold and more than 3 minutes have passed. is not automatically demolded.

(1) The injection molding machine used in this test had a maximum screw rotation speed of 22 rpm, which made it impossible to reduce the metering time (evaluation measure of bite ability) to 3 seconds or less.

(2) In addition, the injection time was set to 4 seconds, and the cooling time was also set to 4 seconds, which were the shortest setting times for the molding machine used. Therefore, it was impossible to evaluate injection moldability (evaluation of crystallization promotion effect, etc.) in 8 seconds or less in this test.

The appearance of the molded product was evaluated in terms of flakiness, sink marks, gloss, whitening, etc. Also, repeat molding 10 times or more under the same conditions,
As the number of repetitions increased, it was observed whether the surface gloss changed or the surface became white. Those with good appearance and no change in appearance even after repeated molding are marked with ``■'', those with good appearance are marked with O1, and those with slightly inferior appearance are marked with △ in each column.

The results are shown in Tables 3 and 4. Table 5 also shows Example 6.
~11. Also, the results of examining the physical properties of the sample obtained in Comparative Example 12 are shown.

The heat distortion temperature was measured in accordance with ASTM-D-648, using a test piece with a thickness of 176 inches and a load of 18.6 kg/am.
It was measured with In addition, the bending test in Table 5 is ASTM-D-
790, the Izot test showed a value determined according to ASTM D-256. Furthermore, flame retardancy was measured according to the flame test of Underwriters Laboratories Bulletin 94 (UL-94).
The flame test was conducted 10 times on five 1.6 mm test pieces. The results are shown in Tables 6 and 7.

From Tables 3 and 4: (1) In the comparative example, the weighing time required 5 seconds or more. Further, the total injection time and mold release time are both 17 seconds or more.

2. In contrast, in the examples, the weighing time is 5 in most cases.
The total injection time and release time was less than 14 seconds, indicating that Sasol wax is an excellent nucleating agent.

3. It was also found that the paraffin waxes Sasol C11 and Sasol H1 have excellent nucleating ability and are more effective as nucleating agents than sodium montanate and the like.

Furthermore, as shown in Examples 17 to 20, when Sasol wax is used as a nucleating agent, even more remarkable effects are exhibited when it is used in combination with other nucleating agents, such as known nucleating agents such as organic acid salts. I also knew that it would happen.

Originally, as shown in Japanese Patent Publication No. 47-13137, paraffin wax was not used as a nucleating agent because the injection cycle was almost twice as high as that of sodium montanate, and the appearance of the product was poor. It was believed that there were no significant effects. However, Sasol H1, CI, which is the same paraffin wax, has a crystallization promoting effect far superior to that of Moncinate sodium salt. Although the reason for this is not clear, Sasol H1, CI has an intermolecular plasticizing effect as a crystal growth agent in addition to its nucleation ability, and can be expected to have an effect of promoting spherulite growth.

Further, although alkali metal salt-based nucleating agents generally have a large effect of promoting crystallization, their use tends to cause a decrease in the degree of polymerization of the polymer, resulting in a decrease in mechanical strength.

On the other hand, paraffin wax-based Sasol H1, CI
The fact that there is no such fear at all is a significant industrial advantage, and it can be expected that molded products with excellent mechanical properties can be obtained.

Table 5 shows Examples 6 to 11. The results of measuring the mechanical properties and heat distortion temperature of the molded product obtained in Comparative Example 12 are shown. In both Example 6 and Comparative Example 12, the mold temperature was 130°.
In contrast to molding at C, Examples 7 to l l C were molded at 100°C.
It was molded in.

As is clear from Tables 3 and 5, when component (B) of the present invention is blended, the biting property and injection moldability do not change even if the mold temperature is lowered, and crystallization occurs even when a high mold temperature is used. It can be seen that a molded product comparable in quality to the comparative example in which a sufficient amount of time was spent on the molded product was obtained.

Examples 21 to 28 and Comparative Example 19 70 parts by weight of PET, 30 parts by weight of glass fiber (C5-3J-941sp manufactured by Nittobo Co., Ltd.) as a reinforcing filler, 2 parts by weight of talc, and 7 parts by weight of decabromo biphenyl oxide as a flame retardant. parts by weight, and 3.5 parts by weight of antimony trioxide were added thereto as shown in Table 6. The extruder (KCK80X2-35
Pellets were obtained by kneading and extruding at 260°C with a VEX x 5) at a discharge rate of about 6 kg/ha.

The pellets were dried at 140° for 0.5 hours in a hot air dryer and then tested.

As is clear from these results, the injection moldability is significantly improved compared to the comparative example. Regarding the biting properties, none of the examples were inferior to the comparative examples, and excellent biting properties and mold release properties were exhibited by adding the additives listed in the table above.

0.75 weight percent of Sasol AI as an additive;
Table 7 shows the results of a test conducted in exactly the same manner as in the example in Table 6, except that ammonium amate was fixed at 0.75% by weight and the type of flame retardant and the ratio with antimony trioxide were varied. Ta.

As a flame retardant, decabromo biphenyl oxide (Table 7
In addition to brominated polystyrene (abbreviated as DBBO)
(abbreviated as BPS in Table 7) was also tested.

Table 7 shows that it is effective to use a combination of different types of nucleating agents in terms of injection moldability and processability. Regarding the biting properties, the measurement time for Examples 24 to 28 was around 4 seconds, and by selecting the type and amount of the nucleating agent, the injection moldability, especially the excellent mold release properties, was significantly improved.

Claims (1)

[Scope of Claims] 1. (a) 100 parts by weight of aromatic polyester resin (component A) and (b) 0.05 to 10 parts by weight of paraffin having an average carbon number of 40 to 100 or its oxygen-containing derivative (component B) An aromatic polyester resin composition. 2. (a) 100 parts by weight of aromatic polyester resin (component A), (b) 0.05 to 10 parts by weight of paraffin having an average carbon number of 40 to 100 or its oxygen-containing derivative (component B), and (c) reinforcing filling. A reinforced aromatic polyester resin composition comprising 5 to 200 parts by weight of component C. 3. (a) 100 parts by weight of aromatic polyester resin (component A), (b) 0.05 to 10 parts by weight of paraffin having an average carbon number of 40 to 100 or its oxygen-containing derivative (component B), (c) Reinforcement filling An aromatic polyester resin composition comprising 5 to 200 parts by weight of a material (component C) and 0.05 to 5 parts by weight of (d) an epoxy compound (component D). 4. The resin composition according to any one of claims 1 to 3, wherein the component B is paraffin having an average carbon number of 45 to 95 or an oxygen-containing derivative thereof. 5. The resin composition according to any one of claims 1 to 3, wherein the component B is paraffin or an oxygen-containing derivative thereof having an average molecular weight of 560 to 1,400. 6. The resin composition according to any one of claims 1 to 3, wherein the B component has a freezing point of 85 to 120°C. 7. The resin composition according to any one of claims 1 to 3, wherein the component B is a carboxyl group-containing derivative or a metal salt thereof having an acid value of 110 KOHmg/g or less. 8. The resin composition according to any one of claims 1 to 3, wherein the C component is a glass fiber having a length of at least 0.2 mm. 9. A container obtained by stretch blow molding the resin composition according to claim 1. 10. A film obtained by melt-molding the resin composition according to claim 1. 11. An openable food tray obtained from the resin composition according to claim 1 or 2. 12. A foam molded product obtained by extrusion foam molding the resin composition according to any one of claims 1 to 3.