JPS60137372A - Seal material - 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 Technical Field The present invention relates to a sealing material that does not deteriorate the organic properties of polyvinyl chloride compositions and has excellent injection workability, electrical insulation properties, etc.

Conventional sealing materials are widely used in fields such as architecture and electrical wiring for the purposes of waterproofing, fireproofing, airtightness, vibration resistance, electrical insulation, and the like.

Various types of base materials are used for sealing materials depending on their purpose. In particular, connecting parts of electric wires, cables, etc.
For terminals, floors, walls, etc., we provide excellent properties such as adhesion to electric wires, cables, etc., electrical properties such as electrical insulation, ease of injection work, waterproofness, airtightness, and vibration resistance. In recent years, sealing materials based on room-temperature curing polyurethane have been widely used.

However, sealing materials based on room-temperature curing polyurethane have m−t+ηr when in contact with electric wires, cables, etc.
, j shi θ) 18th place 1 t 1 ii (eyes I tsume 7 bi 1 μ, I shi 已).

This method has the drawback of causing migration of plasticizer from the plasticizer composition (hereinafter referred to as PVC) and deteriorating the properties of PVC.

Solution: As a result of various studies to eliminate the above-mentioned drawbacks, the present inventor has found that by blending four specific plasticizers into room-temperature curing polyurethane, the migration of the 1lTrffi agent in PVC to the sealing material can be prevented. We have discovered that this can be prevented, and have completed the present invention.

Structure of the Invention The present invention relates to a sealing material characterized in that an IITffi agent having a solubility parameter of 8.6 to 10.0 is blended into a room temperature curing polyurethane.

As the room temperature curing polyurethane in the present invention, any polyurethane conventionally used in this field can be used. Specifically, examples of the liquid polyisocyanate include polymethylene polyphenyl polyisocyanate, methylene diphenyl diisocyanate 1 diphenylmethacydiisocyanate, and the like. The molecular weight of the liquid polyisocyanate is not particularly limited, but it is usually preferably about 200 to 1,500. Further, as the polyol component to be reacted with the liquid polyisocyanate, it is preferable to use liquid polybutadiene having a hydroxyl group at the end. The molecular weight of the polybutadiene is not particularly limited, but it is usually preferably about 500 to 4,000. The ratio of the liquid polyisocyanate to the liquid polybutadiene having a hydroxyl group at the end is preferably within a range such that the ratio of isocyanate group to hydroxyl group is usually about 1:2 to 1:2. The room-temperature curing type polyurethane tongue used in the present invention usually consists of the above two components, but
Depending on the case, a suitable curing agent or the like may be used in combination.

The room-temperature-curing polyurethane used in the present invention preferably has an initial viscosity of about 500 to 15,000 °C at 25°C. Particularly preferably 1,000 °C
It is about ~10,000 Cp1. If it is less than 500 Cl'1, the injection operation is easy, but it is not preferable because it tends to flow out before hardening. Moreover, if it exceeds 15,000 CpS, the pouring workability will deteriorate and hardening may start during pouring, which is not preferable.

In the present invention, it is essential to incorporate a specific iJte agent. Specifically, the solubility parameter (hereinafter referred to as SP) (for example, see [Plasticizers - Seven Theory and Applications JJ', 15-16, published by Kosai Shobo) is 8.6 to 1O.
It is not preferable to use a plasticizer within the range of 10. If a plasticizer is used outside this range, the compatibility with the cold-curing polyurethane will decrease and the plasticizer will easily separate into two liquid phases, which is not preferred. Examples of those that meet this condition include phthalate ester plasticizers such as dimethyl phthalate, diethyl phthalate, and di-n-butyl phthalate;
Aliphatic dibasic acid esters such as diladipate, di-2-ethyl + syl to 4-bacate, etc. can also be used, but tricresyl phosphate, diphenyl cresyl phosphate, trioctyl phosphate, 1 tripto + diethyl phosphate, tri-dibasic acid esters, etc. It is preferable to use adhesives such as chill phosphate and triphenyl phosphate, and acid ester-based sweetfish.

In the present invention, at least one of these is used.

Among these, particularly preferred are tricresyl phosphate and diphenyl sulfur phosphate. It is preferable that the company using the above-mentioned specific 1Uffi agent generally uses about 10 to 35 parts by weight based on 33,100 parts by weight of the room-temperature curing polyurethane. Particularly preferably 15 to 30 parts by weight. If it is less than 10 parts by weight, the effect of preventing the plasticizer in PVC from migrating to the sealing material will not be sufficient, and if it exceeds 35 parts by weight, the compatibility with room temperature curing polyurethane will decrease.
This is not preferable because it tends to separate into a liquid phase.

Additives such as anti-aging agents, colorants, and flame retardants may be added to the sealing material of the present invention, if necessary.

The sealing material of the present invention can be prepared by stirring and mixing liquid polyisocyanate, liquid polybutadiene having a hydroxyl group at the end, the above-mentioned specific sealant, etc. at the time of use, and preparing the sealing material for connecting parts such as electric wires and cables, terminal parts, floors, walls, etc. It can be suitably used for penetrating parts such as.

According to the sealing material of the present invention, the following effects can be obtained.

(1) By blending a specific plasticizer, +Tf q in PVC, which is often used as a covering material for electric wires, cables, etc.
PVC can prevent the agent from migrating to the sealing material.
hardly deteriorates.

(2) Maintains the properties of room-temperature curing polyurethane, such as excellent adhesion to electric legs, cables, etc., electrical properties such as electrical insulation, ease of injection work, waterproofness, airtightness, vibration resistance, etc. are doing.

-7+ Examples and Comparative Examples Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Examples 1 to 5 and Comparative Examples 1 to 5 Sealing materials shown in Table 1 below were prepared.

8- Table 1 (Note) The numbers in the table indicate parts by weight.

The initial viscosity at 25°C when polymethylediporiphenyl polyisocyanate and liquid polybutadiene having a hydroxyl group at the end was mixed was l 100 tl'j.

In each of the above sealing materials, JIS C3342 (1977)
JIS K 6301 (1975) for PVC that satisfies the characteristics of sealing materials for vinyl insulated vinyl sheathed cables.
No. 3 dumbbell punched piece used in the test method (thickness, approximately 1 m)
m) and after the sealing material has hardened, leave it at room temperature or 1
Each sample was left at 00°C for IO days. After being left for 10 days, the PVC was taken out and its elongation and tensile strength were measured to examine the degree of influence on the PVC. The results are shown in Table 2. Table 2 also lists the presence or absence of bleeding (phase separation) of the 1TJlf agent in the sealing material.

As can be seen from Table 2, the sealing material of the present invention has a temperature of 10% at room temperature.
After several days, both the elongation and tensile strength of PVC hardly changed, and it is clear that there was no deterioration. On the other hand, even after 10 days at 100'C (after the accelerated deterioration test), the sealing material of the present invention showed the elongation and tensile strength of PVC compared to Comparative Examples 1 and 2! l) It is clear that the change in TMi is small and that deterioration is suppressed.

c and above)

Claims (1)

[Scope of Claims] (1) A sealing material characterized in that a plasticizer having a solubility J\rameter of 8.6 to 1000 is blended with room temperature curing polyurethane tough. (2) Room temperature curing polyurethane contains liquid polyisocyanate and liquid polybutadiene having a hydroxyl group at the end, and has an initial viscosity of 500 to 150 at 25°C.
00 tllE. The sealing material according to claim 1. ■ The sealing material according to claim 1 or 2, in which 10 to 35 parts by weight of a plasticizer is blended with 100 parts by weight of room-temperature-curing polyurethane, 1) The plasticizer is a phosphate ester type 11' Claim 1, which is an iJ plastic agent;
The sealing material according to item 2 or 3.