JPS6142562A - Resin composition for interior and exterior finish of automobile - Google Patents

Abstract

PURPOSE:To provide the titled resin compsn. having excellent rigidity and resistanct to impact and marring, by blending a linear satd. polyester, a block copolyester and a rubber reinforced resin in a specified ratio. CONSTITUTION:A linear satd. polyester (A) (polytetramethylene terephthalate content: at least 70wt%), a block copolyester (B) composed of 10-60wt% arom. polyester derived from an arom. dicarboxylic acid (alkyl ester) and a 2-12C aliph. glycol and 90-40wt% aliph. polyester derived from a 2-12C aliph. dicarboxylic acid and a 2-12C aliph. glycol, and a rubber reinforced resin (C) [rubber component (mainly conjugated diolefin polymer) content: 40-80wt%] are blended together in such a proportion as to give a weight ratio of A/B/C represented by formulas I and II.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a resin composition for the exterior and interior of automobiles, which is based on thermoplastic polyester and has improved properties.

(Prior Art) Various molding materials having high impact resistance and excellent cold resistance and heat resistance, as well as excellent paintability, have been proposed. Specifically, 911 is a resin composition made of a rubber reinforced resin, a distoner such as polyether amide, polyester ether, and polybutylene terephthalate.
Japanese Patent Publication No. 50744 discloses a resin composition comprising polybutylene terephthalate, polyester ether, and an acrylic rubber reinforced resin, and Japanese Patent Publication No. 55-56249 discloses a resin composition comprising polybutylene terephthalate, polyester ether, and acrylic rubber reinforced resin.

(Problems to be Solved by the Invention) However, even if the material has excellent impact resistance, cold resistance, paintability, etc., it is currently difficult to function as a molding material for the exterior and interior of automobiles.

This is because molding materials for automobile exteriors and interiors may be used with or without painting, so the properties required of these molding materials are not just impact resistance and paintability, but also heat resistance and scratch resistance. Please also request.

However, in order to impart high impact resistance to polyvarnish, the above-mentioned polyester ether or rubber reinforced resin t-polyester compounded has the problem that as impact resistance increases, heat resistance rigidity and scratch resistance decrease. .

(Means for Solving the Problems) In view of the above-mentioned current situation, the present inventors have conducted extensive studies to obtain a molding material for automobile exteriors and interiors that has excellent impact resistance*, paintability, heat-resistant rigidity, and scratch resistance. As a result, a block copolymer consisting of a linear saturated polyester mainly composed of polytetramethylene terephthalate, a specific aromatic polyester component and an aliphatic polyester component, and a rubber reinforcing resin containing a conjugated diolefin as a rubber component The present invention was achieved by discovering that by blending the ingredients within a certain range, it is possible to obtain a resin composition for automobile exteriors and interiors that has contradictory properties such as impact resistance, rigidity, and scratch resistance.

The present invention comprises a linear saturated polyester (A) containing at least 70% by weight of polytetramethylene terephthalate, an aromatic polyester component (b-1 ) and an aliphatic polyester component (b-2) consisting of an aliphatic dicarboxylic acid having 2 to 12 carbon atoms and an aliphatic glycol having 2 to 12 carbon atoms (
B) and a rubber reinforced resin (C) containing 40 to 80% by weight of a rubber component mainly composed of conjugated diolefin, in which components (A), trunk) and (C) have the following weight ratio:
This is a resin composition for automobile exteriors and interiors that is blended so as to always satisfy formulas I) and (II).

It is important to use a linear saturated polyester containing polytetramethylene terephthalate Y as the main component in Kinei I:IJ. For example, if polyethylene terephthalate is used, the heat resistance of the resulting molded product may decrease,
Depending on the molding temperature, there is a tendency for significant sink marks to occur in the molded product, resulting in a marked deterioration in appearance.

Akira Kinie's gray linear saturated polyester (T) contains at least 70% by weight of polytetramethylene terephthalate which is polycondensed from terephthalic acid or its alkyl ester and 1,4-butanediol; Examples include those copolymerized with other dicarboxylic acid components or diol components up to 30% by weight, or those blended with other polyalkylene terephthalate Y.

Furthermore, in the block copolymer of the present invention, aromatic dicarboxylic acid or its alkyl ester and a carbon number of 2 to 12
The aliphatic glycol or aromatic polyester component (
b-1) and an aliphatic polyester component (b-2) consisting of an aliphatic dicarboxylic acid having 2 to 12 carbon atoms and an aliphatic glycol having 2 to 12 carbon atoms, and an aromatic polyester component. Block copolymer 0 of (b-1)
), the content in the range is 5 to 6 aot, preferably 10 to 6
0 fold #, excellent. Aliphatic polyester component (b-2)
Specific examples include polyethylene adipate, polytetramethylene adipate, polyethylene sepacate, polyneopentyl sebacate, polyhexamethylene azelate, poly-ε-caprolactone, and the like.

As mentioned above (it has been known that polyester ether block copolymers have been used as a component of molding materials, and when used, the effect of imparting impact resistance is large. Therefore, the present invention Odor [If the block copolymer (B) used is used instead of the polyester ether block copolymer, it is thought that it is necessary to increase the aliphatic polyester component in order to obtain the same effect, and the effect is only the same. However, it was thought that the linear saturated polyester (A)
When used in combination with rubber-reinforced resin (C), it exhibits a different effect than conventional ones, and has higher impact resistance than conventional ones. (The resin composition can be made into a resin composition with excellent abrasion resistance, and can be provided with excellent properties not previously available.)

Further, the rubber reinforced resin (C) in the present invention is obtained by graft polymerizing a resin component to a rubber component mainly composed of conjugated diolefin, and the content of the rubber component in the rubber reinforced resin is 40 to 80% by weight. It is something. Here, examples of the rubber component include polybutadiene or a butadiene-butyl acrylate copolymer, a butadiene-styrene copolymer, a butadiene-acrylonitrile copolymer, etc. in which the butadiene content in the rubber component is 80% by weight or more. Examples of resin components graft-polymerized to the rubber component include vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; aromatic vinyl compounds such as styrene, α-methylstyrene, and vinyltoluene; acrylic acid alkyl esters;
At least one type of methacrylic acid alkyl ester is used. If the content of the rubber component in the rubber reinforced resin is less than 40% by weight, the effect of improving impact resistance tends to be insufficient.
Moreover, if the amount exceeds 80% by weight, the heat resistance stability tends to decrease, which is not preferable.

The resin composition of the present invention includes the above (A), (B) and (C).
Each component is always blended within a range that satisfies formulas (I) and (A) above, and if the weight ratio of component (i) in the total resin composition is less than 0.3, the heat resistance will deteriorate. If the decrease tends to be large, and if it exceeds o, a?:, the impact resistance tends to decrease, which is not preferable.The preferable t ratio of the (a) component in this total resin composition is 0. 5～
It is 0.7.

In addition, in the resin composition of this @mei, the (ton) component and the (C
) component weight ratio is also an important requirement, (B) / (C
) weight ratio is 1/10<(B)/(C)<2/3
, preferably 1/6<(B)/(c)<1/
2, and if this weight ratio is less than 1/10, the heat resistance rigidity will tend to decrease significantly, and if it is more than 2/3, the impact resistance and paintability at low temperatures will tend to decrease, which is not preferable.

Known methods can be used to prepare the resin composition of the present invention, for example, sufficiently dried (A), non and (
The resins of each component of C') are mixed in an amount that satisfies the above formula (I) and α■)2, or a predetermined amount of each of (g), (B) and (C) is mixed. How to feed the component resins to a melt extruder, mix them together, and then injection mold a sample into a berent shape? : Can be used as appropriate.

The resin composition of the present invention may optionally contain a phenol, a phosphite thread stabilizer, a prtt type agent such as ethylene bisstearamide, rice fatty acid ester wax, an ultraviolet absorber, a filler, a modifier, and a dye. Pigments etc. can be added.

(Example) The present invention will be specifically explained below using Examples.

In each of the Examples and Comparative Examples, the evaluation of physical properties was carried out at ℃ according to the following method.

Izont impact strength ASTM D2 with impact resistance
56 at 23°C.

Heat-resistant rigidity: Flexural modulus at 80° C. was measured in accordance with ASTM D790.

Heat distortion temperature: 1/4” (thickness) x 1/2” (width)
xs" (length 9 specimen yal-ASTMD648 at a load of 66 psi.

Paintability After baking urethane paint on two specimens at 120°C for 30 minutes, cross-cuts of 100 squares were made with one width, and the state of peeling was examined in a peel test using cellophane tape. In addition, deformation after painting was visually observed. Judgment was based on the following criteria.

◎: No peeling or deformation at all.

○: Complete (no peeling but deformation) Or 1 to 2 peelings out of 100 squares do.

×: 6 or more peelings occur or changes occur. The shape is dog-like.

Scratch resistance: A lead wire with a hardness of H was drawn on the surface of the molded product, and it was evaluated whether the surface was resistant to scratches.

Example 1, Comparative Examples 1 to 6 Linear saturated polyester <A) Intrinsic viscosity [η] as component
polytetramethylene terephthalate with a polytetramethylene terephthalate of 105, the block copolymer (B) component is composed of 55% by weight of polytetramethylene terephthalate component and 45% by weight of polytetramethylene adipate component [η]
is a polyester block copolymer of ilO, and the rubber reinforcing resin (C) component is 60% by weight of polybutadiene, 14% by weight of niacrylotrile, and 26% by weight of styrene.
ABS resin '1 is 1 which is graft-polymerized with a large amount of weight and is blended in the proportions shown in the table.
The mixture was melted and mixed in a pent extruder with a diameter of 65° C. and shaped into a pellet shape. Each of the obtained pellet 't cylinders was injection molded at a temperature of 250°C and a mold temperature of 50°C to obtain test pieces for evaluation.

Various physical properties were evaluated using these evaluation specimens.

These results are shown in Figure 1.

In Table 1, Comparative Examples 1 to 5 lack one of the constituent components of the present invention, and Comparative Example 6 contains 55% by weight of polytetramethylene terephthalate as a hard component instead of the block copolymer of the present invention. , polytetramethylene oxide 45% with a molecular weight of about 1200 as a soft component
%, and the other resins were the same as in Example 1 and Comparative Examples 1 to 5.

As is clear from the results in Table 1, the molded products obtained from the resin compositions of the present invention exhibit significantly high impact resistance that cannot be predicted from Comparative Examples 1, 2, 4, 5, etc. It can be seen that it has excellent heat cutting resistance and paintability. Also, comparative example 6
Comparing the results of 5 and 5, it can be seen that the resin composition of the present invention exhibits higher impact resistance and provides higher heat-resistant rigidity than the use of a general polyester ether Pronk copolymer.

Furthermore, when the scratch resistance of each of the molded products of Example 1 and Comparative Example 6 was evaluated, the molded products of Example 1 were not easily scratched.

On the other hand, the one of Comparative Example 6 was scratched.

Examples 2 to 5, Comparative Examples 7 to B The polytetramethylene terephthalate used in Example 1 was used as the linear saturated polyester (A) component, and the polytetramethylene terephthalate component was 45% by weight as the block copolymer (B) component. A polyester block copolymer composed of 55% by weight of a polytetramethylene separate component was mixed with 15.8% by weight of acrylonitrile and 4t2. Example 1 ABS resin graft-polymerized with ii% was blended in the proportions shown in Table 2.
Various evaluation specimens were prepared in exactly the same manner as described above, and various physical properties were evaluated. These results are shown in Table 2. ~ Examples 6 to 8, Comparative Examples 9 to 10 Intrinsic viscosity [η] as linear saturated polyester (A) component
(L88 polytetramethylene terephthalate (PB)
Polyethylene terephthalate (PET) 'l'j with a limiting viscosity [η] of [180
) A polyester pronk copolymer t consisting of 60 fi amount of polytetramethylene terephthalate component and 40 weight percent of polycaprolactone component having an average molecular weight of 5000, and 765 wt % polyptadiene as the rubber reinforced resin (C) component. MBS resin obtained by graft polymerization of methyl methacrylate 1sxis and styrene 20M 1k% was prepared by changing the weight ratio of component (A)/component (C) as shown in Table 3 and was mixed in exactly the same manner as in Example 1 at various degrees Celsius. Evaluation specimens were prepared and various physical properties were evaluated.

These results are shown in Table 3.

In addition, in place of the amount of PBT used alone in Example 70, PET/PB
When the same amount of a mixture of T=60/40 (weight ratio) was used, the impact resistance was poor at 12 mm/α/crn.

(Effects of the Invention) The resin composition of the present invention has the above-mentioned taroki ti'j D brother, which improves the spoon resistance at low temperatures by 7% and 10%.
Even at high temperatures of 0°C or higher, the blade's rigidity decreases to a very low level, and it has excellent paintability and resistance to damage to molded products, making it an excellent cedar additive for automobile exteriors and interiors.

Claims (1)

[Scope of Claims] A linear saturated polyester (A) containing at least 70% by weight of polytetramethylene terephthalate, an aromatic dicarboxylic acid or an alkyl ester thereof, and a carbon number of 2 to 12
Aromatic polyester component consisting of aliphatic glycol (
a block copolymer (B) of b-1) and one aliphatic polyester component (b-2) consisting of an aliphatic dicarboxylic acid having 2 to 12 carbon atoms and an aliphatic glycol having 2 to 12 carbon atoms; Consisting of a rubber reinforced resin (C) containing 40 to 80% by weight of a rubber component mainly composed of olefins,
The weight ratio of components (A), (B) and (C) is as follows (I
1. A resin composition for automobile exteriors and interiors which is blended so as to always satisfy formulas ) and (II). (A) 0.3≦(A)/[(A)+(B)+(C)]≦0.8
...(I)1/10<(B)/(C)<2/3...
・(II)