JPS58206663A - Polyester composition - Google Patents

Abstract

PURPOSE:The titled composition having extremely improved warpage deformation such as inner warp, twist of a box or channel shaped molded article, improved molding properties, etc., obtained by blending a polyester with an amorphous or spherical inorganic filler together with a fibrous reinforcing agent and a nucleating agent for crystallization. CONSTITUTION:30-72wt% polyester (preferably >=0.4 intrinsic viscosity) having at least >=80mol% ethylene terephthalate repeating unit is blended with 8- 50wt% fibrous reinforcing agent (preferably glass fibers having <=30mu diameters and 0.1-5mm. length), 19.8-60wt% amorphous or spherical inorganic filler (especially wollastonite) having 2-15mu average particle diameters, and 0.2-5wt% nucleating agent for crystallization having <=10mu average particle diameter (preferably 0.1-5mu) selected from talc, mica, titanium oxide, and carbon black in a molten state. The addition of an ester of a higher fatty acid and an alcohol is preferably to improve releasability, surface gloss of a molded article, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyester composition, and 1 further relates to a polyester composition which is particularly effective in preventing warp deformation such as internal warpage and twisting in box-shaped or channel-shaped molded products. It is to serve.

Polyethylene terephthalate has excellent mechanical properties, thermal properties*, and chemical resistance, and is useful as a material for forming films and other materials. It is well known that when used as a molded article, a composition reinforced with a reinforcing agent such as glass 11 talc is used to improve the rigidity. However, when molding a box-shaped or channel-shaped molded article from such a reinforced composition, the molded article has a disadvantage that it is susceptible to warping deformation such as internal warping and twisting.

As a result of intensive research, Akira Motoba et al. aimed to obtain a molding material that is a reinforced composition and has improved warp deformation.
An ester composition according to the present invention has been achieved.

That is, the present invention is a polyester containing at least 80 mol % of polyester 30 to 72 mol%.
Heavy jIt%1 Fibrous reinforcing agent 8-501izm%1 Amorphous or Vi spherical inorganic filler with an average particle size of 2-15μ19.
A crystallization nucleating agent with an average particle size of 8 to 60% and talc, mica, titanium oxide, and carbon black with an average particle size of 10μ or less J11
% of polyester composition.

The polyester composition according to the present invention has a feature that warping deformation such as inner warp twisting in box-shaped or channel-shaped molded products is extremely small. It also has many features such as excellent mechanical properties and island formability.

The polyester used in the present invention is a copolymerized polyester containing polyethylene terephthalate repeating units of at least 80 mol % or more, preferably 90 mol % or more. As Kyodosei ingredients, conventionally known facial ingredients and/or glycol ingredients can be used. In other words, acid components such as #-t as copolymerization components, such as isophthalic acid, naphthalene 1,4- or f'i2,6-dicarboxylic acid, diphenyl ether 4,4-dicarboxylic acid, and adipine 1 sebacin version. Glycol components such as , propylene glycol 1 butylene glycol) diethylene glycol 1 neopentyl glycol, cyclohexane dimetatool, 2,2-bis(4-hydroxyphenyl)propane sp-oxybenzoate 1 topyl p-hydroxyethoxybenzoic acid Examples include oxyacids such as Note that the polyester preferably has an intrinsic viscosity of 0.4 or more, more preferably 0.5 or more, as measured at 30°C using a phenol/tetrachloroethane mixed solvent (6/4 ratio) bath solution. It is particularly preferable. Further, the polyester may be partially branched to the extent that moldability is not impaired. It may also be a blend of two or more polyesters having different intrinsic viscosities.

Examples of the fibrous reinforcing agent used in the present invention include glass fiber 1 carbon or graphite fiber 1 metal carbide fiber 1 gold nitride MIa fiber 1 silicon carbide fiber 1 each bale whisker 1 hardened phenol-formalin fiber) aramid bond, etc. . However, one particularly preferred is the glass fiber. The diameter of the fiber is 30μ or less, preferably 1
~10μ. The fiber length is 41! On average, the diameter is about 0.1 to 5 m (although it varies depending on the type, added wrinkles, etc.), and preferably the main fiber is 0.1 to 0.6 M fiber.

If it is too short, the toughness will decrease and the reinforcing effect will decrease. The fibrous reinforcing agent is preferably treated with a treatment agent such as a silane yarn coupler, a titanium coupler, etc. in the case of glass fiber to improve its dispersibility in polyester or its adhesion to polyester.

Examples of the amorphous or spherical inorganic filler having an average particle diameter of 2 to 15 microns used in the present invention include wollastonite, calcium carbonate) glass powder, etc., and wollastonite is particularly preferred. The filler may also be subjected to surface treatment to improve its dispersibility in polyester and its adhesion to polyester.

Conventionally, a molding material e containing plate-shaped talc, mica, and glass has been known.) It has the disadvantage of causing internal warping and warping deformation at the end of the i-type molding. The present invention solves these drawbacks by mainly incorporating a specific amount of an amorphous or spherical inorganic filler.

Furthermore, in the present invention) moldability 1 coating surface characteristics, etc.

In order to improve the average particle size (10 μ or less), particularly preferably
．． A crystallization nucleating agent comprised of 1 to 5 μm of talc, mica, and titanium oxide A carbon black is blended.

The composition of the above components in the polyester composition V of the present invention '11j is 30 to 72 mm% of polyester, 8 to 50 m% of fibrous reinforcing agent, and 19.8 to 60 m% of inorganic filler.
]k% and crystallization nucleating agent are 0.2 to 53kM%. If the amount of fibrous reinforcing agent is too small, the strength and rigidity of the molded product will be insufficient, and if it is too large, the elongation at break of the molded product will decrease, resulting in a brittle compound. In addition, if the inorganic filler is too small, warp deformation will be large, and if the inorganic filler is too large, the fluidity during molding will decrease, resulting in a decrease in the elongation at break of the molded product, resulting in a decrease in toughness and deterioration of the surface properties. Furthermore, if the amount of the crystallization nucleating agent is too small, the moldability and surface characteristics of the molded product will be poor, and if it is too large, the warp deformation i will become large.

The composition of the present invention contains esters of higher fatty acids, such as fatty acids having 15 to 50 carbon atoms, and alcohols in order to improve surface gloss etc. of molded products. It is preferred to incorporate salts with MA group metals and mixtures thereof.

Specific examples include sodium stearate, magnesium stearate, calcium stearate, and calcium montan acid ester.

The compositions of the present invention may optionally further contain organic crystallization promoters such as polyalkylene glycols, mono- or diethers or mono- or diesters of polyalkylene glycols, aromatic carboxylic acid esters of mono- or polyhydric alcohols, and #1. Metal salts of aromatic acid (1 benzophenone)
Carbo>g Gold m Base-containing polymer etc. 1 Flame retardant such as carbonate ester oligomer of halogenated bisphenol 1 Cyanuric acid ester oligomer of halogenated bisphenol etc. Combustion aid such as antimony compound Crosslinking agent such as glycol diglycidyl ether 1 (polyalkylene glycol diglycidyl ether) bisphenol diglycidyl ether, etc.) Stabilizers such as antioxidants, ultraviolet absorbers, impact modifiers such as aromatic polyester polyether lepidic body 1 aromatic: & group polyester aliphatic polyester elastomer , rubber-like g IJ mama-) yI1 coloring agents into which ionic groups or reactive groups have been introduced, and other yuzu additives can be blended. Further, other thermoplastic resins such as AT may be additionally blended in an amount that does not depart from the gist of the present invention.

The method for producing the composition of the present invention is not particularly limited, and any method may be used. For example, a method in which polyester and all other components are mixed in advance and compounded using an extruder. 1. All components except the polyester and rutted fiber reinforcement are mixed and put into an extruder. 1. The molten material is poured into a glass 4-bing, etc. After cooling, the wire is cut into suitable lengths.The so-called electric wire wrapping method. Examples include a method of mixing the entire composition\a method of blending a fibrous reinforcing agent-containing polyester and another filler-containing polyester.

However, the mixing timing of the first mixing method is not necessarily limited to these.

The composition thus obtained provides molded products with excellent moldability and surface properties not only in high-temperature molding but also in low-temperature molding. It can be widely used for molding multi-layer containers, etc., but is particularly suitable for molding box-shaped or channel-shaped molded products when excellent warpage resistance is not taken into account. If necessary, the low-temperature molded product can be subjected to post-heat treatment to crystallize it and stabilize its heat resistance.

The present invention will be explained below with reference to Examples. In addition, 1% in the examples is %.

Practical example Polyethylene terephthalate (viscosity 0.60), glass chopped strands with a length of 3 mm and a diameter of 10 μm), talc (crystal nucleating agent) with an average particle size of 3 μm, and various inorganic fillers were tumbled in the proportions shown in Table 1. Mixed in a blender.

Next, put it into the hopper of a 4011 + 3φ vent type extruder and use a cylinder of 7M degrees (from the hopper side) 250-2
Funbound chips of each composition were produced by melt-kneading L1 at 70-280°C.

The obtained compound chips were dried at 120°C for 4 hours under reduced pressure and then molded into a cylinder using an injection molding machine.
70-265-270℃, mold temperature 120℃, injection pressure holding time 15 during paper cooling A [15 seconds, injection pressure 50 to 9
/C- long side 70m57 side 5C++am19sa20th,
A box-shaped product with a thickness of 2 mm and the shape shown in Figure 1 was molded.The resulting molded product was left at room temperature for 24 hours, and the maximum internal sill dimension A (see Figure 2) of the long side plate was measured. The degree of internal warping was determined.

The results are shown in Table 1.

At that time, it was confirmed that a molded article with small warp deformation and excellent physical properties was obtained using the composition of the present invention.

[Brief explanation of drawings]

FIG. 1 is a sketch of a box-shaped molded product made from a polyester composition according to the present invention in order to evaluate internal wrinkles. Also 1
FIG. 2 is an explanatory diagram showing a measurement site A of internal shavings after the box-shaped molded product shown in FIG. 1 has been left for 24 hours. Patent applicant: Toyobo Co., Ltd.

Claims (1)

[Scope of Claims] L Low ethylene terephthalate repeating units 8
Polyester of 0 mol% or more 30-72 m Lid % S Fibrous reinforcement 8-50 % Weight 1 Amorphous or spherical inorganic filler with an average particle size of 2-lfiμ 19.8-60 Iris-% and talc) Mica A polyester composition comprising 0.2 to 5 [1%] of at least one crystallization nucleating agent selected from the group of monodispersed titanium and carbon black and having an average particle size of 10 μ or less. Wollastonite is a regular or spherical inorganic filler.
2. The polyester composition according to claim 1, which is at least one polyester blended with calcium carbonate and glass powder. The polyester composition according to claim 2, wherein the amorphous or spherical inorganic filler is wollastonite.