JPS6172050A - Polyester resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition having low warpage, excellent mechanical properties and smooth surface, by compounding a thermoplastic polyester with titanium dioxide having specific particle diameter. CONSTITUTION:(A) 100pts.wt. of a thermoplastic polyester is compounded with (B) 10-250pts.wt. of titanium dioxide having an average particle diameter (d) of 0.8-9mums. The particles having diameter falling within (d-0.5mu)-(d+1.0mum) account for >=50(wt)%, preferably >=65% of the whole component B. The component A is selected from a resin containing 3-50% aliphatic dicarboxylic acid copolymerized polyester, a resin containing 0.5-40% olefinic copolymer having glycidyl group, and a resin containing 3-50% polyester elastomer.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polyester resin composition that exhibits less molding warpage, excellent mechanical properties, and excellent surface appearance.

<Conventional technology> Polyester resins such as polybutylene terephthalate have significantly improved strength and rigidity by adding reinforcement and fillers, and are widely used in fields such as electrical machinery, automobiles, and building materials. It is being Generally, reinforcing/filling agents that have such a reinforcing effect, such as glass fiber and mica, have a fibrous or plate-like shape, so they have the disadvantage of causing large mold warp deformation to the molded product. It is well known that it has

In addition, the appearance of the molded product loses its smoothness due to the presence of these fillers, and it cannot be used at all in applications where molded appearance and surface smoothness are important.

Such granular fillers with low anisotropy (e.g. calcium carbonate, clay, diatomaceous earth, calcium metasilicate, talc, sericite, etc.) are used to improve molding properties.
A method of adding
Although these methods have the effect of reducing molding warpage, they have the disadvantage that mechanical properties deteriorate, a practically sufficient effect cannot be obtained, and surface smoothness is not improved at all. The reality is that there are.

<Problems to be Solved by the Invention> Therefore, the present inventors solved the drawbacks of these conventional techniques, namely, the extremely poor mechanical properties represented by impact resistance and the surface smoothness of the molded product, and developed a molded product. As a result of intensive studies to obtain a polyester resin composition with low adhesiveness, excellent mechanical properties such as impact resistance, and excellent surface smoothness of molded products, we found that thermoplastic polyester resin and specific Particle size
The inventors have discovered that the above object can be effectively achieved by a composition containing titanium dioxide having the following properties, and have arrived at the present invention.

Means and operation for solving the problems> That is, the present invention provides: (1) titanium dioxide having an average particle size (smallest in the range of 0.8 to 9 μm, based on 100 parts by weight of al thermoplastic polyester) It is a polyester resin composition comprising 10 to 250 parts by weight of titanium dioxide, and in a preferred embodiment, the titanium dioxide contains particles (d:
A polyester resin composition having a particle size distribution in which the effective particle diameter (μm) is 50% by weight or more of the total, the thermoplastic polyester is aliphatic dicarboxylic acid copolymerized polyester
A polyester resin composition containing ~50M'A%, and a polyester resin composition in which the thermoplastic polyester contains 0.5 to 40% by weight of a grylzyl group-containing olefin copolymer, and a polyester resin composition in which the thermoplastic polyester contains a polyester elastomer. The object of the present invention is to provide a polyester resin composition containing 3 to 50% by weight.

The thermoplastic polyester used in the present invention is 90 mol%
The above is a polymer obtained by condensation polymerization of a dicarboxylic acid component, which is a terephthalic acid component, and a diol component.

The terephthalic acid component mentioned here is terephthalic acid and its ester-forming derivatives, and other dicarboxylic acid components used together with the terephthalic acid component include isophthalic acid, orthofucric acid, 2,6-naphthalene dicarboxylic acid, 1. 5-naphthalene dicarboxylic acid, bis(p-carboxymphenyl)methane, anthracene dicarboxylic acid, 4,4'-; phenyl dicarboxylic acid, 1.
Aromatic dicarboxylic acids such as 2-his(phenoquino)ethane-4,4'-dicarboxylic acid, 5-sodium sulfoisophthalic acid, arepic acid, sepanonic acid, azelaic acid,
Aliphatic dicarboxylic acids such as dodecanedioic acid, 1°3-
Preferred examples include alicyclic dicarboxylic acids such as noclohexanedicarboxylic acid and 1,4-noclohexanedicarboxylic acid, and ester-forming derivatives thereof.

In addition, the diol component preferably has 2 to 20 carbon atoms.
aliphatic glycols such as, for example, specifically ethylene glycol, propylene glycol, 1,4-butanediol, neopenotyl glycol, 1,5-pentanodiol, 1,6-hexanediol, decamethylene glycol, noclohexane Preferred examples include remethanol, nclohexanodiol, and ester-forming derivatives thereof.

Preferred specific examples of these polymers or copolymers include polybutylene terephthalate, polybutylene (terephthalate/inophthalate), polybutylene (terephthalate/adipate), polybutylene (terephthalate/sebacate), and polybutylene (terephthalate/inophthalate).
decaredicarboxylate), polyethylene terephthalate, polyethylene (terephthalate/isophthalate), polyethylene (terephthalate/adipate), polybutylene (terephthalate 15-sodium sulfoisophthalate), polyethylene (terephthalate 15-
Due to the moldability of the polyester resin composition, polybutylene terephthalate, polybutylene (terephthalate/adipate), polybutyreno (terephthalate/decaledicarboxylate), polyethylene terephthalate, polyethylene (terephthalate/adipate), etc. Polybutylene (15-sodium terephthalate sulfoisophthalate) and the like are particularly preferably used. In addition, these thermoplastic polyesters were prepared by heating a 0.5% O-chlorophenol solution at 25°C.
Relative viscosity when measured at 12-2.01, especially 13-2.01
Those in the range of L85 are preferred.

Moreover, these can be used in combination of two or more types.

The titanium dioxide used in the present invention is anatase type and rutile type manufactured by the sulfuric acid method or the chlorine method and has a purity of 9.
Titanium dioxide of 5% or more is preferably used.

It is necessary that the average particle diameter of titanium dioxide is in the range of 0.8 to 9 μm, and L5 to 6 μm is particularly preferably used.

Here, the average particle size is expressed as a particle size corresponding to an integrated particle size distribution Mfjk of 50% by weight.

In order to obtain even better effects of the present invention, the particle size distribution of titanium dioxide particles should be d (μm), which is expressed as H-o, s≦d≦H+x, o (where a: average particle diameter (μm)). The content of particles with a particle size (effective particle content) of 5
It is preferably 0% by weight or more, particularly preferably 65% by weight or more.

The particle size distribution of the particles here is determined from the particle size distribution measured by the sedimentation balance method.

In order to exhibit the effects of the present invention, it is necessary that the average particle size of titanium dioxide satisfies the above range. Outside this range, when the average particle size is less than 0.8 μm, the surface smoothness is good but the resistance is Impact resistance is poor, and the warp deformation of the molded product becomes large, which is undesirable. If the average particle size exceeds 9 μm, the impact resistance and surface smoothness will be poor, which is not preferable. Also,
Regarding the particle size distribution, if the effective particle content is less than 50% by weight, the molded product will have a large degree of warpage and its impact resistance will be poor, which is not preferable.

The amount of titanium dioxide added is 10 to 250 parts by weight per 100 parts by weight of the polyester resin! Parts by weight, particularly 30 to 100 parts by weight, are preferred. If the amount is less than 10 parts by weight, the rigidity of the resin will be insufficient. If it exceeds 250 parts by weight, the impact resistance will be poor and the surface smoothness of the molded product will be poor, which is not preferable.

When the thermoplastic polyester of the present invention contains an aliphatic dicarboxylic acid copolymer polyester, better impact resistance can be imparted.

The aliphatic dicarboxylic acid copolyester herein refers to 3 to 50 mol%, preferably 10% by mole of the dicarboxylic acid component.
It is a copolymer consisting of a dicarboxylic acid and a diol component, of which ~40 mol% is an aliphatic dicarboxylic acid component. The aliphatic dicarboxylic acid components include adipic acid, sebacic acid, acelaic acid, decanedionic acid, dodecanedioic acid, hexadecanodioic acid, octatothiodionic acid,
Preferred examples include dimer acids and ester-forming derivatives thereof. Other dicarboxylic acid components used together with these aliphatic dicarboxylic acid components include terephthalic acid, inophthalic acid, orthophthalic acid, 2,6-
Knack dicarboxylic acid, 1,5-knack dicarboxylic acid, bis(p-carboxyphenyl)methane, anthracenocarboxylic acid, 4,4'-diphenyldicarboxylic acid, 1,2-bis(phenoxy)ethane-4, Preferred examples include aromatic dicarboxylic acids such as 4'-dicarboxylic acids, alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, and ester-forming derivatives thereof. It will be done. In addition, diol components include aliphatic glycols having 2 to 20 carbon atoms, such as ethylene glycol, propylene glycol,
1.4-butanediol, neopentylg-11col,
Preferred examples include 1,5-bentanediol, 1,6-hexanereol, decamethylene glycol, cyclohexanemethanol, cyclohexanereol, and ester-forming derivatives thereof.

Preferred specific examples of these copolymers include polybutyreno (terephthalate/adipate), polybutylene (terephthalate/sebacate), polybutylene/(terephthalate, /power/dicarboxylate), polybutyreno (terephthalate/isophthalate/sebacate),
Examples include polybutyreno (terephthalate/inofucrate/decanecarboxylate), polyethylene (terephthalate/adipate), polyethylene (terephthalate/sebacate), and the like.

In addition, aliphatic nocarbono acid copolyester is 0.5
% 0-chlorophenol solution measured at 25°C has a relative viscosity of 1.2 to 2.0, especially 1.3 to 1.85.
Preferably, it is within this range.

Moreover, these can be used in combination of two or more types.

%, especially 5 to 45% by weight. If the amount is less than 3% by weight, the effect of improving impact resistance will be small, and if it exceeds 50% by weight, the inherent heat resistance of the thermoplastic polyester will be impaired, which is not preferable.

When the thermoplastic polyester of the present invention contains a Grindyl group-containing olefinic copolymer, better #4 impact strength can be imparted.

The Grindyl group-containing olefin copolymer here preferably includes 50 to 99.5% α-olefino and 1% α-olefino by weight.
, β-unsaturated unsaturated carbobic acid lulue x 5- #5
0-0.5% by weight and vinyl acetate 0-49.5% by weight
It is a copolymer consisting of Here, the α-olefin is preferably ethylene, propylene, butene-1, etc., and ethylene is particularly preferably used. Also, α
, glinodyle ester of β-unsaturated carboxylic acid preferably has the general formula (wherein R is a hydrogen atom or a lower alkyl atom).
(representing a kill group), specific examples include glycinol acrylate, glycinol acrylate, glycinol acrylate, etc. Among them, glycinol acrylate is preferably used.

α in the olefin copolymer containing a glycyl group,
The copolymerization amount of grillyl ester of β-unsaturated carboxylic acid is suitably 0.5 to 50% by weight, especially 1 to 20% by weight; if it is less than 0.5% by weight, the effect of the present invention cannot be obtained. ,
Moreover, if it exceeds 50% by weight, the composition tends to gel during melt-kneading, which is not preferable.

As specific examples of the olefin copolymer having a Grinrel group, ethylene/prindyl methacrylate copolymer and ethylene/glinodyl methacrylate/vinyl acetate copolymer are preferably mentioned.
~30% is preferred. If it is less than 0.5% by weight, the effect of improving impact resistance will be small, and if it exceeds 40% by weight, the inherent heat resistance of the thermoplastic polyester will be impaired, which is not preferable.

When using a grindyl group-containing olefinic copolymer, organic sulfonate metal salts such as sodium dodecylbenzenesulfonate and sodium tothinyl sulfonate, and alcohols such as lauryl sulfate sodium salt should be used. A small amount of sulfuric acid ester salt or the like can be added together, and the effect of improving impact resistance is further exhibited by the addition of these.

When the thermoplastic polyester of the present invention contains a polyester elastomer, better impact resistance can be imparted.

The polyester elastomer herein refers to a polyether ester block copolymer, a polyester/ester block copolymer, preferably consisting of an aromatic polyester as a hard segment and a poly(alkylene oxide) glycol and/or aliphatic polyester as a soft segment. , polyether ester/ester block copolymer. The aromatic polyester constituting the hard segment is a polymer obtained by condensation polymerization of a dicarboxylic acid component □, of which 60 mol% or more is a terephthalic acid component, and a diol component. As the dicarboxylic acid component other than terephthalic acid and the diol component, those mentioned for the thermoplastic polyester can be used.

Preferred examples of the aromatic polyester include polyethylene terephthalate, polybutylene terephthalate, polyethylene (terephthalate/inophthalate), polybutylene (terephthalate/inophthalate), and the like.

In addition, specific examples of poly(alkylenoxide) glycol and aliphatic polyester constituting the soft segment include polyethylene glycol, poly(1,
2- and 1,3-propylene oquinodo) glycol,
Poly(tetramethylene oxide) glycol, copolymer of ethylene oxide and propylene oxide, copolymer of ethylene oxide and tetrahydrofuran, polyethylene alebate, polybutylene adipate, poly-ε-caprolamine, polyethylene sebacate, poly Preferred examples include butyrenosebacate.

The ratio of soft segment to polyester hard segment in polyester elastomer is 95 in heavy toxicity ratio.
It is preferably from 15 to 10/lo, especially from 90/10 to 30/70.

Specific examples of polyester elastomers include polyethylene terephthalate and poly(tetramethylene oxide).
Glycol block copolymer, polyethylene terephthalate/isophthalate, poly(tetramethylene oxide) glycol block copolymer, polybutylene terephthalate/poly(tetramethylene oxide) glycol block copolymer, polybutylene terephthalate/ino Phthalate/poly(tetramethylene oxide) glycol block copolymer, polybutylene terephthalate/decalcarboxylate/poly(tetramethylene oxide) glycol block copolymer, polybutylene terephthalate/poly(propylene oxide/ethylene) poly(propylene oxide) glycol block copolymer, poly(propylene oxide) glycol block copolymer, poly(propylene oxide) glycol block copolymer, poly(propylene oxide) glycol block copolymer, poly(propylene oxide) glycol block copolymer, poly(propylene oxide) glycol block copolymer, polybutylene terephthalate/te'carboxylate
Propylene oquinide/ethylene oquinide) glycol block copolymer, polybutylene terephthalate/poly(
(ethylene oxide) glycol block copolymer, polybutylene terephthalate/polyethylene anopate block copolymer, polybutylene terephthalate/polybutylenoarpate block copolymer, polybutylene terephthalate O polybutylene sebacate block copolymer Union,
Preferred examples include polybutylene terephthalate/poly-ε-caprolactonoblock copolymer.

Among these polyester elastomers, especially polybutylene terephthalate and poly(tetramethylene oxide)
Glycol block copolymer, polybutylene terephcrate,/inophthalate/poly(tetramethylene oxinodo) glycol block copolymer, polybutylene terephthalate 1-0 poly(propylene terephthalate/ethylene oxide) glycol block copolymer Polymer, polybutylene terephthalate/inophthalate poly(propylene oxide/ethylene oxide) glycol block copolymer,
A polybutylene terephthalate/polybutylene arepate block copolymer and a poly-ε-caprolacto block copolymer of polybutylene terephthalate are preferably used.

Also, 1)llt of these polyester elastomers
The relative viscosity measured in the same manner as the jjE thermoplastic polyester is preferably in the range of 1.4 to 4.0, particularly 1.6 to 3.0.

These polyester elastomers can be used in a combination of 2f or more.

Especially 5 to 45 Shigekawa% is pora. If it is less than 3%, the effect of improving impact resistance is small, and if it exceeds 50%, the inherent heat resistance of the thermoplastic polyester is undesirably impaired.

Furthermore, the thermoplastic polyester of the present invention is an aliphatic dicarboxylic acid copolyester, a glycyl group-containing olefin/
2 selected from copolymers and polyester elastomers
It is also possible to simultaneously contain more than 50 iQΦ for the combination with the thermoplastic polyester.

In preparing the composition of the present invention, zinc oxide, magneum oxide, silicon oxide, potassium titanate, magnonium carbonate, carbonate, carbonate, carnoium metasilicate, barium sulfate, talc, etc. Fillers such as , kaolin, clay, glue, mica, asbestos, siloid, glass beads, glass baluno, norasbal-7, and fibrous reinforcing agents such as glass fiber, metal fiber, carbon fiber, etc. can be added as necessary. can. In addition, other usual additives such as lubricants, mold release agents, nucleating agents, plasticizers, flame retardants, heat stabilizers, ultraviolet absorbers, pigments,
Dyes and other thermoplastic resins and the like may also be added as desired.

The method for producing the composition of the present invention is not particularly limited, but for example, raw materials containing thermoplastic polyester, titanium dioxide having a specific particle size, and other additives are supplied to a screw extruder, and melt extrusion mixing is performed. Methods such as that can be adopted.

The composition of the present invention can be made into a molded article having a desired shape by employing any resin molding method such as injection molding, extrusion molding, or blow molding.

The composition of the present invention is a thermoplastic polyester blended with titanium dioxide particles having a specific particle size, which not only reduces the adhesiveness of molded products but also improves mechanical strength and surface smoothness. Improvements can be made at the same time.

The fields of application in which these compositions can be used are as described above.
This is a field that requires small deformation of the product, high physical properties, and true surface appearance (surface smoothness), such as precision mechanical parts such as watches and cameras, and parts of Cheaply Coke, Hiteo, Stereo, and Konopiyuk. Examples include electrical and electronic equipment parts, wind louvers, door handles, fuel lids, and other automobile parts. Furthermore, performance can be improved by using it as a base for high-order processed products, such as painted products and resin-plated products.

(Example> The effects of the present invention will be further explained below with reference to Examples.

In addition, each abbreviation in an Example means the following.

PBT polybutylene terephthalate PBT/A:
Polybutyreno (terephthalate/alebate) (terephthalic acid component/adipic acid component copolymerization molar ratio = 80,
'20) I) BT/S: Polybutyreno (terephthalate/sebacate) (terephcuric acid component, 'sebacic acid component copolymerization molar ratio = 80/20) [) BT/'D-1 polybutyreno (terephthalate/sebacate)
(terephthalic acid component/decalcarboxylic acid component copolymerization molar ratio = 80/20 >PB
T/D-2: Polybutyreno (Terefucrete 7/Tekarki Lupokilt) (Same as above, copolymerization molar ratio = E7GM
Aniethylene/grillyl methacrylate copolymer (polymerization ratio = 907' I O) E7GN1A7/VA
・Ethylene, 'griryzyl methacrylate-l-5 vinyl phosphate' (proper polymer (copolymerization weight ratio = 82/12.7'C)
) 1) BT -PTl'l/fG Polybutylene terephthalate/poly(tetramethylene oxide) glycol block copolymer (noftsegmento/hard segment weight ratio = 40/60) P BT/ I-PTMG/polybutylene (terephthalate/ Polyte 1-lamethylene oxinodoglycol bronoc copolymer (terephthalic acid component/'
Inophthalic acid component copolymerization molar ratio = 70, '30, noftosegmento/hard segmento ffl ffl ratio = 20 Examples 1 to 8 4'
PBT) l O0 parts by weight are triblended with titanium dioxide having the average particle size surface and particle size distribution (effective particle size particle content: expressed in dS) shown in Table 1 in the proportions shown in Table 1. were melt-mixed and pelletized using an extruder with a 40-M* screw set at 250''C.

Next, the obtained pellet was subjected to an injection molding machine set at 250'C, and the mold temperature was 125JIJ at a mold temperature of 80°C.
A disk molded product (test piece A) with a thickness of Iρ×2 mm and a test piece (
Test piece B) was molded.

For the molding paste, use the test piece A as a test sample, statically harden the test sample 1 on the reference surface 2 as shown in FIG. ? L
Measure the clearance (g) from the basic surface 2 of another point 4 on the circumference in the '73 direction, and check the clearance (g) directly? The molding paste was evaluated as t, expressed as a percentage of the size of the mold. (The effective amount of molding paste is 0.5% or less.

) Impact resistance of 11゜ was evaluated by measuring the Aijino) Bi''R strength of test piece B.

The one-mouth lubricity of the molded product was determined by measuring the surface roughness of test piece A using a surface roughness meter manufactured by Tokyo Seimitsu Co., Ltd. The surface smoothness was expressed and evaluated using the difference (Rmax) between the highest and lowest portions of the surface irregularities that were actually measured. (Effective surface smoothness is Rmax = 2
．． Q Itm or less. ) These evaluation results are the first
Shown in the table.

Comparative Examples 1 to 9 Polybutylene terephthalate (PB) with a relative viscosity of 1.57
T) 100 parts by weight of the various fillers shown in Table 1 were triblended in the proportions shown in Table 1, and this was pelletized in the same manner as in Example 1. Performance was subsequently evaluated in the same manner as in Example 1.

These results are shown in Table 1.

Examples 9 to 23, Comparative Examples 10 to 11 Polybutylene terephthalate (PB) with a relative viscosity of 1.57
T) and the aliphatic recarponoic acid copolymerized polyester shown in Table 2 were triblended in the proportions shown in Table 2, and further the average particle diameters shown in Table 2 (mountain, particle size molecule lj (
After tri-blending titanium dioxide having a particle content of effective particle size (represented by ds) in the ratio shown in Table 2, this was melt-mixed under the same conditions as in Example 1 and pelletized. Continuously, the amount of molding paste, impact resistance,
Surface smoothness was measured and evaluated.

These results are shown in Table 2.

Examples 24-35, Comparative Examples 12-13 Polybunarenoterephthalate (PB) with a relative viscosity of 1.57
T) and the glycyl group-containing oleolene copolymer shown in Table 3 were dry-breaded to the proportions shown in Table 3, and the average particle diameter (d) and particle size distribution (effective particle size After dry-topping titanium dioxide having a particle content (expressed as ds) in the proportions shown in Table 3, the mixture was melt-mixed and pelletized under the same conditions as in Example 1. Subsequently, the amount of molding paste, impact resistance, and surface smoothness were measured and evaluated (curved) using the same fj method as in Example 1.

These results are shown in Table 3.

Examples 36-47, Comparative Examples 14-15
(PBT) and the polyester elastomer shown in Table 4 are triblended in the proportions shown in Table 4, and the average particle size and particle size distribution (effective particle size particle content: After tri-blending titanium dioxide having dS) at the proportions shown in Table 4, this was melted and combined under the same conditions as in Example 1 to pelletize. Continuing, molding paste 1i! in the same manner as in Example 1! , impact resistance, and surface smoothness were measured and evaluated.

These curves 17J are shown in Table 4.

As is clear from the results in Tables 1 to 4, the polyester composition of the present invention has balanced molding warpage prevention properties, impact resistance, and surface smoothness compared to conventional filler-reinforced polyester compositions. It is excellent.

<Effects of the Invention> The polyester composition of the present invention produces a molded article having small molding paste, excellent mechanical properties, and a smooth surface appearance.

[Brief explanation of drawings]

FIGS. 1 and 2 are diagrams showing an apparatus for measuring the amount of molding paste in an example. FIG. 1 is a plan view, and FIG. 2 Reference plane S' fixing device 4 Clearance patent applicant Azuma Co., Ltd. Figure 1 Figure 2

Claims (5)

[Claims] (1) Polyester made by blending (b) 10 to 250 parts by weight of titanium dioxide with an average particle size (@d@) in the range of 0.8 to 9 μm to (a) 100 parts by weight of thermoplastic polyester. Resin composition. (2) Titanium dioxide @d@-0.5≦d≦@d@+1
．． 2. The polyester resin composition according to claim 1, which has a particle size distribution in which particles having a particle size of 0 (d: effective particle diameter μm) account for 50% by weight or more of the entire composition. (3) The polyester resin composition according to claim 1, wherein the thermoplastic polyester contains 3 to 50% by weight of aliphatic dicarboxylic acid copolymerized polyester. (4) The polyester resin composition according to claim 1, wherein the thermoplastic polyester contains 0.5 to 40% by weight of a glycidyl group-containing olefin copolymer. (5) The polyester resin composition according to claim 1, wherein the thermoplastic polyester contains 3 to 50% by weight of polyester elastomer.