JPH01308618A - Tube made of vinyl chloride resin - Google Patents

Abstract

PURPOSE:To obtain a tube having heat distortion resistance, high impact resilience and excellent fabricating properties by molding the tube by a partially crosslinked vinyl chloride resin, a copolyester resin and a vinyl chloride resin composed of a plasticizer. CONSTITUTION:A tube made of a vinyl chloride resin consists of a 100pts.wt. vinyl chloride resin, which is made up of a 8-90wt.% polyvinyl chloride gel section insoluble to tetrahydrofuran and composed of a tetrahydrofuran soluble section as the remainder, a 10-200pts.wt. copolyester resin and a 25-200pts.wt. plasticizer. The copolyester resin displays no effect when it is added in 10pts.wt. or less, and adhesion onto a kneading machine is increased and workability is deteriorated when it exceeds 200pts.wt. A partially crosslinked vinyl chloride resin composition used is mixed with the plasticizer, a stabilizer, etc. by a mixer, and kneaded and granulated by a Bunbury, a roll, an extruder, etc. The tube can be prepared through injection molding, extrusion molding, blow molding and press molding in the same manner as a general vinyl chloride resin from granulated pellets, and performance excellent in heat distortion resistance and impact resilience can be acquired.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a tube molded from a vinyl chloride resin composition having heat deformation resistance and high impact resilience.

<Prior Art> Generally, rubber is mainly used for applications that require heat deformation resistance and high impact resilience. The reason for this is that it has heat deformation resistance and high rebound resilience, which are the characteristics of rubber. However, tubes using rubber require a vulcanization process, which increases the number of man-hours, and the material cannot be recycled. In order to overcome the drawbacks of these rubbers, soft vinyl chloride resin or thermoplastic elastomer resin is used in some of the tubes, but because they are thermoplastic resins, they have low heat deformation resistance and creep resistance. Due to its poor performance, its range of use was limited.

<Problems to be Solved by the Invention> In view of this situation, the present inventors have developed a material that has heat deformation resistance and high impact resilience similar to rubber, but has processability similar to that of general thermoplastic resins. As a result of extensive research, we have found that it can be used as a vinyl chloride resin that is a blend of a vinyl chloride resin containing a polyvinyl chloride gel component that is insoluble in tetrahydrofuran (hereinafter referred to as partially crosslinked vinyl chloride resin) and a copolyester resin. It is surprising that tubes molded from the vinyl chloride resin composition have heat deformation resistance and high impact resilience close to those of rubber, yet can be molded in the same way as general thermoplastic resins. After discovering this fact, we have completed the present invention. An object of the present invention is to provide a tube molded from a vinyl chloride resin composition that has heat deformation resistance and high impact resilience close to those of rubber, but also has moldability similar to that of general thermoplastic resins. be.

Means for Solving the Problems> That is, the present invention is a tube molded from a vinyl chloride resin having heat deformation resistance and high impact resilience, which is made of a partially crosslinked vinyl chloride resin, a copolyester resin, and a plasticizer. .

Due to the general shape of the tube, the molding method consists in blending a copolyester resin with the partially crosslinked vinyl chloride resin inside. This makes it possible to manufacture tubes with heat deformation resistance and high impact resilience using the same molding method as that used for thermoplastic resins. Although the crosslinked portion in the resin component is not specified, from the viewpoints of heat deformation resistance, high impact resilience, and processability, it is appropriate that the crosslinked portion is between 8% and 90% by weight.

Examples of copolyester resins include polybutadiene terephthalate for the hard segment, and poly(alkylene oxide) glycols that can be used for the soft segment, including those in which the alkylene group has 2 to 10 carbon atoms;
For example, poly(ethylene oxide) glycol, poly(1,2-
and 1.3-propylene oxide) glycol, poly(tetramethylene oxide) glycol, poly(pentamethylene oxide) glycol, poly(hexamethylene oxide) glycol, poly(heptamethylene oxide) glycol, poly(octamethylene oxide) glycol, poly(nonamethylene oxide) glycol,
and poly(l,2-butylene oxide) glycol; random or block copolymers of ethylene oxide and 1,2-propylene oxide, and formaldehyde in glycols such as propylene glycol;
Alternatively, it includes poly-formals prepared by reacting with a mixture of glycols, such as a mixture of tetramethylene and pentamethylene glycol.

Regarding the amount of copolyester resin added, if it is less than 10 parts by weight, there is no effect at all.200! When the fi content exceeded 1 part, good impact resilience and workability were exhibited in the range of 30 parts by weight or more and 90 parts by weight or less.

In the composition of the present invention, the plasticizer is added to impart rubber elasticity to the obtained molded article and to improve impact resilience, and the amount added varies depending on the intended use of the molded article. However, if the amount of plasticizer is too small, high-temperature melting and high-pressure molding will be required, making processing difficult, and the resulting tube will be brittle and have poor appearance. On the other hand, if the amount of plasticizer is too large, the plasticizer will boil out of the resulting tube, causing problems in workability and practicality such as stickiness, which is not preferable. Examples of such plasticizers include alkyl esters of aromatic polybasic acids such as dibutyl phthalate, dioctyl phthalate, and butylbenzyl phthalate; alkyl esters of aliphatic polybasic acids such as dioctyl adipate, dioctyl azelate, and dioctyl sebacate; Examples include alkyl esters of phosphoric acid such as tricresyl phosphate, polyesters, and the like.

The vinyl chloride resin composition used for the tube of the present invention can be used as is, but it may be blended with other thermoplastic resins, rubber, heat stabilizers, fillers, pigments, processing aids, etc. as necessary. used. Other thermoplastic resins include general vinyl chloride resin, ethylene vinyl acetate copolymer, ethylene vinyl chloride copolymer, urethane vinyl chloride copolymer, chlorinated polyethylene, ABS resin, AS resin, urethane resin, acrylic. type resin etc., but as rubber, NB
R, CR, etc. are used.

The partially crosslinked vinyl chloride resin composition used in the tube of the present invention can be granulated and molded by the same process as conventional vinyl chloride resins.

That is, it is mixed with a plasticizer, a stabilizer, etc. using a mixer such as a super mixer or a blender, and then kneaded and granulated using a Banbury, roll, extruder, or the like.

Of course, even in the form of a mixed powder, there is no difference in molding process from conventional vinyl chloride resins. Granulated pellets can be made into tubes by injection molding, extrusion molding, blow molding, and press molding in the same way as general vinyl chloride resins, and the moldability is also good like general vinyl chloride resins. However, the resulting tube can exhibit superior heat deformation resistance and impact resilience compared to general vinyl chloride resins.

Example 1 A vinyl chloride polymer (manufactured by Sumitomo Chemical, UX
-C) 100 parts by weight, 90 parts by weight of dioctyl phthalate, barium zinc stabilizer (manufactured by Adeka Argus, AP
-539) and each part of a copolyester resin (Hytrel 4057, manufactured by DuPont East) were added, and the mixture was kneaded with a Banbury mixer to form pellets. Presunto was made from the pellets and evaluated for thermal deformation, rebound resilience, and workability.

Table 1 Note 1 Productivity evaluation was determined by comprehensively judging the adhesion to the Banbury mixer and the state of adhesion to the rolls.

Good: Good workability with no adhesion.

Fairly good: There is some adhesion to the kneading machine.

Poor: Severe adhesion to the kneading machine and poor workability.

Note 2: Heat-resistant shape retention was evaluated by measuring the heat deformation rate U Is-6723) of the pressed product.

-Note 3: Resilience conforms to JIS K 6301.

As is clear from these results, the copolyester resin
Those using ~200 parts by weight obtained good impact resilience, workability, and heat deformation resistance, and particularly good results were obtained in the range of 30 to 90 parts by weight.

Example 2 The compositions of experiment numbers 1 and 5 used in Example 1 were heated to 50+o
A molded product having an outer diameter of 12 mm and an iron core of 6 mm in the center was extruded using an extruder using a cross die.

In order to investigate the heat deformation resistance of this tubular molded product,
Cut into lengths of 100mm, leave horizontally in an oven at 160℃, apply a load of 1kg to the length of 100W+m for 1 hour, then take it out to room temperature and check the degree of deformation of the molded product after removing the load. did. The results are shown in Table 2.

Table 2 <Effects of the Invention> The tube of the present invention has good moldability similar to ordinary vinyl chloride resin tubes, and also has properties similar to rubber in terms of heat deformation resistance and high impact resilience. Used in automobiles, especially for covering iron wires such as cable conduits, piping tubes in engine rooms, home appliances, protective cover tubes for electric wires, construction, food heads, etc., and the interior is used for transporting liquids, gases, and tanks. Also used for parts.

Claims (1)

[Claims] (1) Heat-resistant polyvinyl chloride gel insoluble in tetrahydrofuran, consisting of 8 to 90 parts by weight and the remainder soluble in tetrahydrofuran, consisting of 100 parts by weight of vinyl chloride resin, 10 to 200 parts by weight of copolyester resin, and 25 to 200 parts by weight of plasticizer. PVC resin tube with deformation and high rebound resilience.