JPS5930182B2 - resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a block copolymer composition made by blending porous silica gel with a block copolymer. The present invention provides a block copolymer resin composition that imparts slip properties to sheets and films when molded into sheets and films.

Films and sheets made of block copolymers of styrenic hydrocarbons and conjugated diene hydrocarbons have poor aperture properties when forming the film by the inflation method due to poor sliding properties between the films and between the sheets. This makes it difficult to convert a double shape into a single shape (single winding is not possible), and furthermore, when used in a double shape, the opening cannot be opened, making it impractical.

In addition, when the sheets are processed into containers such as cups and trays, there is no slipping when the containers are stacked and pulled out one by one from the top to fill the containers. Furthermore, the container has poor removability (stackability), which significantly impairs workability, and poor slip properties are a major cause of trouble when feeding sheets into a molding machine during secondary processing. The present invention has developed a block combination of styrenic hydrocarbon and conjugated diene hydrocarbon that maintains the excellent transparency and printability of styrenic resin itself while improving the slipperiness, which is a drawback of such resin. The present invention relates to polymer compositions.

Organic lubricants such as fatty acid amides are used as lubricating agents for block copolymers of styrene hydrocarbons and conjugated diene hydrocarbons. is insufficient, the opening property during inflation is insufficient, and the stackability of the vacuum-formed container is poor.

Moreover, if a large amount is added, poor adhesion of the printing ink will occur, making it difficult to put it to practical use. As a result of studies to improve these drawbacks, the present inventor found that styrenic hydrocarbons of 50 to 9
For a block copolymer containing 5 wt% of styrene hydrocarbon and conjugated diene hydrocarbon, the pore volume O
, Iml/V or more and an average particle size of 0.5 to 20 μ
It has been found that by blending 0.01 to 2 PHR of porous silica gel, it imparts excellent lubricity and does not impair the excellent transparency and printability of the resin itself.

As such silica gel, Fuji Davison Chemical K. K
．． It is possible to make products such as thyroid (product name). The porous silica gel used in the present invention has a pore volume of 0.1 d/
Preferably, particles with a large surface area of r or more, 0.11
If it is less than 1LI/7, practically preferable lubricity cannot be imparted.

Furthermore, even if the porous silica gel has a pore volume of 0.1 m1/r or more, if the average particle size is less than 0.5 μm, the lubricity will be insufficient, and if the average particle size is 20 μm or more, the film obtained even if the amount added is the minimum. Also, the haze of the sheet increases and the transparency deteriorates, which is unfavorable in terms of appearance.

The preferred particle size range is 0.7 to 10 microns, and the most preferred range is 1 to 5 microns. The amount of porous silica gel added is in the range of 0.01 to 2 PHR, preferably 0.1 to 0.3 PHR, since too much will adversely affect transparency, and too little will not impart sufficient lubricity. Most preferably, it is added in a range of 0.05 to 1.0 PHR. In the present invention, a block polymer is a resin obtained by copolymerizing a styrene hydrocarbon and a conjugated diene hydrocarbon into a block shape using an organolithium compound as a polymerization initiator, and is a copolymer containing 50 to 95 wt% of a styrene hydrocarbon. It is a polymer.

The styrenic hydrocarbons mentioned here include styrene, α-methylstyrene, etc., and the conjugated diene hydrocarbons include butadiene, isoprene, etc. The above-mentioned porous silica gel is added to the PROC copolymer by a commonly used blending method, for example, the PROC copolymer and porous silica gel are uniformly blended in a pen shell mixer, and the mixture is then passed through an extruder.

In carrying out the present invention, known antistatic agents, stabilizers,
There is nothing wrong with adding a lubricant, a coloring agent, and a thermoplastic resin that is compatible with the block copolymer of the present invention.

The present invention will be further explained below with reference to Examples.

Example 1 A block copolymer having a block structure of styrene-butadiene-styrene and containing 80 wt% styrene was sufficiently uniformly mixed with various porous silica gels using a pen shell mixer, and then put into an extruder to form pellets. Then, a film was formed using an inflation method using a 65' extruder to produce a film with a thickness of 25 μm.

Table 1 shows the opening property, sliding angle, and Hazel printability of the obtained film.

Table 1 shows that the pore volume is 0.1 m1/y or more and the average particle size is 0.
．． 0.01-2PHR of 5-20μ porous silica gel
It has been shown that the addition of this compound provides openability and slipperiness, and does not impede the transparency and printability of the resin. Example 2 Porous silica gel (pore volume 1.
6m2/r, average particle size 3.2μ) was added at 0.3PHR and mixed using a pen shell mixer, which was made into pellets using an extruder, and then a sheet with a thickness of 0.3% was obtained using the T-die method. .

The sliding angle between the sheets and the transparency of the obtained sheet were measured.

This sheet is then processed into a single-shot vacuum forming machine manufactured by Illich.
A round cup of 00CC was made and its stackability was investigated.

For comparison, a similar test was conducted on a resin to which no porous silica gel was added.

Claims (1)

[Claims] 1 For a block copolymer consisting of a styrenic hydrocarbon and a conjugated diene hydrocarbon containing 50 to 90 wt% of styrenic hydrocarbon, the pore volume is 0.1 ml/g or more and the average particle size is 0.5 to A resin composition containing 0.01 PHR to 2.00 PHR of porous silica gel having a diameter of 20 μ.