JPH04214749A - Polypropylene resin composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polypropylene resin composition, and more particularly to a polypropylene resin composition that has improved heat shrinkage of fiber molded articles and is useful for nonwoven fabric products.

0002

BACKGROUND OF THE INVENTION Polypropylene has excellent mechanical properties and is effectively used in a wide range of fields such as injection molded products and extrusion molded products. In order to improve the moldability of polypropylene used for fibers, methods are used to increase the melt flow rate (hereinafter referred to as MFR) by adding organic peroxides during the polymerization stage or during pellet molding. ing. Furthermore, as a technique for improving the thermal shrinkage rate, a method is generally used to increase the crystallinity of the polymer by reducing the xylene soluble content.

0003

[Problems to be Solved by the Invention] The above-mentioned polypropylene resin with improved fluidity greatly improves the moldability of fibers, but it is difficult to perform heat treatment in post-processing such as crimping and twisting, and in non-woven fabric molding. There is a problem that fiber shrinkage occurs due to this. When fiber shrinkage occurs, it causes problems in the processing of textile products and nonwoven fabric products.

0004

[Means for Solving the Problems] As a result of intensive studies to solve the above-mentioned drawbacks of polypropylene resin compositions with improved fluidity, the present inventors have developed a method of blending specific compounds into polypropylene resins. The inventors have discovered that the above-mentioned drawbacks can be overcome by doing so, and have come to propose the present invention.

That is, the present invention provides polypropylene resin 1
0.03 to 0.00 parts by weight of trimellitic acid ester
This is a polypropylene resin composition containing 5 parts by weight.

The resin composition of the present invention can prevent heat shrinkage even in polypropylene resins whose fluidity has been improved by conventionally known methods, and does not impair moldability such as spinning and drawing properties. .

[0007] The polypropylene resin used in the present invention is
Propylene homopolymer or propylene content 7
Copolymers consisting of 0% by weight or more of propylene and one or more α-olefins such as ethylene, butene, and pentene, vinyl acetate, vinyl chloride, etc., and blends of these polymers and other polymers. used.

[0008] As the trimellitic acid ester used in the present invention, a trialkyl ester is preferably used. Among these, trioctyl trimellitate and triisodecyl trimellitate are preferably used.

[0009] The blending ratio of the above trimellitic acid ester may be appropriately selected depending on the application, but it is preferably 0.03 to 5 parts by weight, particularly 0.05 to 5 parts by weight of the trimellitic acid ester per 100 parts by weight of the polypropylene resin. A proportion of 3 parts by weight is preferable because the effects of the present invention are exhibited very markedly. In addition, the antioxidant 3,9-bis[2-{3-(3-t-butyl-4-hydroxy-
5-methylphenyl)propionyloxy}-1,1-
Dimethylethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane and polypropylene resin 10
When used together in the range of 0.01 to 1 part by weight relative to 0 part by weight, the effect of the invention becomes even more remarkable, and this is a preferred embodiment of the invention.

The polypropylene resin composition of the present invention may also contain other antioxidants, antistatic agents, lubricants, dispersants, light stabilizers, ultraviolet absorbers, nucleating agents, clarifying agents, Additives such as flame retardants and metal deactivators can also be blended within ranges that do not impede the effects of the present invention.

The polypropylene resin composition of the present invention can be kneaded and molded by conventional methods to obtain desired molded articles. Alternatively, a desired molded article can be obtained by applying, adsorbing, or permeating trimetate ester onto the surface of a resin pellet.

0012

Effects of the Invention According to the present invention, fibers molded using a polypropylene resin composition have extremely low shrinkage due to heat. Therefore, according to the present invention, shrinkage of the fibers is suppressed even during post-processing such as crimping and twisting, and heat treatment during nonwoven fabric molding, making it possible to obtain fibers that are easy to process.

[0013]

[Examples] The present invention will be explained in detail below based on Examples, but the present invention is not limited to the following Examples. The measurement methods used in the following Examples and Comparative Examples are shown below. 1) Measurement of heat shrinkage rate After the drawn fibers (fiber length: 50 cm) were left in a dryer heated to 130°C for 30 minutes, the length of the fibers was measured, and the heat shrinkage rate was determined using the following formula. Heat shrinkage rate (%) = {[50 (cm) - Fiber length after heating (cm) / 50 (cm)} x 100 2) Spinning-drawing test (fiber formability) 40 mmφ melt-spinning molding machine (resin temperature: A fiber (10 denier) was formed at 290°C, winding speed: 500 m/min), and the fiber was passed through a drawing machine (stretching temperature: 130°C, drawing speed: 1st roll 15 m/min, 2nd roll).
The film was stretched 4 times (2.5 denier) at 60 m/min). Formability was evaluated based on the presence or absence of yarn breakage during spinning and drawing.

Examples 1 to 13 and Comparative Examples 1 to 7 The compounds shown in Table 1 were blended with 100 parts by weight of a polypropylene resin and thoroughly mixed in a Henschel mixer. The resulting mixture was heated to a resin temperature of 230 using a 50 m/mφ extruder.
Pelletized at °C. Next, the obtained pellets were used to form fibers of 10 denier using a melt spinning molding machine, and were stretched 4 times using a drawing machine to create drawn fibers of 2.5 denier. The above-mentioned heat shrinkage rate was measured using this drawn fiber. The measurement results of fiber formability and heat shrinkage rate are collectively shown in Table 1.

Furthermore, as a comparative example, the compounds shown in Table 2 were blended and the same procedure as above was carried out, and the results are shown in Table 2. The polymers and additives used are as follows. A: 3,9-bis[2-{3-(3-t-butyl-4-
Hydroxy-5-methylphenyl)propionyloxy}-1,1-dimethylethyl]-2,4,8,10-
Tetraoxaspiro[5.5]undecane: Sumil
Izer GA80 Sumitomo Chemical B:1,3,5-
Trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene: Irganox 1330 Ciba-Geigy C: Pentaerythritol-tetrakis [3-(3,5-di-t-t)
-butyl-4-hydroxyphenyl)propionate} :Irganox 1010 Ciba Geigy D:1,
3-bis-(t-butylperoxy-isopropyl)-
Benzene: Perkadox 14 Kayaku Akzo E:
Trioctyl trimellitate: Sansocizer TO
TM New Japan Chemical F: Triisodecyl trimellitate: Sansocizer
TITM Shin Nihon Rika Polypropylene [both homopolymer and random copolymer, pentaerythritol tetrakis (β-lauryl thiopropionate):: Sumilizer TPD (Sumitomo Chemical) 0.20 parts by weight and calcium stearate (NOF) 0.05 parts by weight Polyethylene: Sumitomo Chemical Excellen V
L800 Polybutene-1: Mitsui Petrochemical Polybutene-1
M8510

[0016]

[Table 1]

[0017]

[Table 2]

Claims (1)

[Claims] 1. A polypropylene resin composition comprising 0.03 to 5 parts by weight of trimellitic acid ester per 100 parts by weight of polypropylene resin.