JPS6081234A - Rubber composition having low impact resilience - Google Patents

Abstract

PURPOSE:To provide a composition having extremely high slip resistance even in wet state, and exhibiting excellent impact and oscillation absorbing property, by mixing a styrene-butadiene copolymer having high styrene content with a general-purpose rubber, adding a reinforcing agent, etc. to the mixture, and curing with heat. CONSTITUTION:The objective composition having an impact resilience of 0-30% can be produced by compounding (A) 100pts.wt. of a rubber mixture composed of (i) a styrene-butadiene copolymer having high styrene content wherein the styrene-content is adjusted to 45-70(wt)%, preferably 55-65% by the polymerization or blending process and (ii) 5-65%, preferably 20-50% general-purpose rubber based on the whole rubber mixture, with (B) 0-100parts of a filler, (C) 5-80parts of a reinforcing agent, (D) 0-60parts of a plasticizer and (E) a vulcanizing agent and a vulcanization accelerator, and curing the composition by heating at 110-180 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a low-resilience rubber composition that has an impact resilience of 0 to 30% over a wide temperature range, and more specifically, for use in rubber grips that have extremely non-slip properties even when wet with water. The present invention relates to a low-resilience rubber composition that can be particularly suitably used as a material for.

In general, one of the important performance requirements for a grip is that it is non-slip. This is very important for safety when using tools equipped with this grip, such as tool fighting machines.

Leather, rubber, etc. have traditionally been used as materials for grips, but recently rubber grips have become mainstream in various fields due to their cost and ease of use. Natural rubber or synthetic rubber compositions having a glass transition temperature of 120° C. or lower have been used as raw material rubber for rubber grips. However, although this type of material # has sufficient slip resistance when the grip is dry, it becomes extremely slippery once it gets wet. This becomes a serious defect when used outdoors or when the user's hands get sweaty.

The present inventors previously discovered and proposed a rubber composition that exhibits low impact resilience of 30% or less in a wide temperature range of -10 to 50°C, but recently, a rubber composition that exhibits low impact resilience of 30% or less in a wide temperature range of -10 to 50°C has recently been developed. I discovered that special P1 is extremely hard to slip even when wet. However, the previously proposed rubber compositions had problems in mechanical properties such as strength for use in particularly severe applications as materials for grips.

In view of the above circumstances, the present inventors will continue their research by increasing the amount of reinforcing agent in order to measure the direction of mechanical properties, and in order to prevent the resulting low impact resilience from decreasing The above reinforcement is applied to a mixed rubber made by mixing a high styrene content styrene-butadiene copolymer adjusted to a styrene content of A specific amount of oil and a filler are added to the mixture, followed by a vulcanizing agent and a vulcanization accelerator.
It is possible to obtain a rubber composition that exhibits low impact resilience of 0% to 30% in a wide temperature range of 50°C, has extremely low slip properties even when wet with water, and has improved mechanical properties such as strength. This discovery led to the present invention.

In addition, the low-resilience rubber composition of the present invention has extremely low slip properties even when wet with water, and also exhibits excellent shock and vibration absorption performance. It also has the effect of alleviating shock and vibration applied to the main body of machines, tools, etc.

As mentioned above, the low-resilience rubber composition of the present invention has the property of being extremely hard to slip even when wet with water, and has the effect of mitigating shock and vibration, so it can be suitably used as a material for rubber grips as described later. However, other uses 1. For example, anti-slip surface materials for roads and floors, acoustic components such as turntable rubber sheets, vibration damping materials, shock absorbing materials,
Vibration damping materials, vibration isolation materials, sound insulation materials, table tennis racket face materials,
It can also be suitably used for protectors, helmets, etc.

The present invention will be explained in more detail below.

The low resilience rubber composition of the present invention comprises: (a) A: A high styrene-containing 11-styrene-butadiene copolymer whose styrene content is adjusted to 45 to 70% by weight through a polymerization process or blending B: Fully mixed rubber Mixed rubber of high styrene content styrene-butadiene copolymer and general purpose rubber consisting of 5 to 65% by weight of general purpose rubber (b)i 0 to 100 parts by weight of filler per 100 parts by weight of synthetic rubber (C) Reinforcing agent in an amount of 5 to 80 parts by weight per 100 parts by weight of mixed rubber (d) Plasticizer in an amount of 0 to 60 parts by weight per 100 parts by weight of mixed rubber (e) Vulcanizing agent/vulcanization accelerator It is a rubber composition obtained by heating and curing a mixture consisting of the following, and has an impact resilience of 0 to 30%.

As mentioned above, the high styrene content styrene-butadiene copolymer (a) of the component (a) (mixed rubber) needs to have a styrene content of 45 to 70% (the same applies below weight%). However, it is particularly preferable that it is 55 to 65%. In addition, when obtaining the above-mentioned styrene-butadiene copolymer with a high styrene content, it can be obtained by blending styrene-butadiene copolymers having various different styrene contents. It is suitably obtained by blending a styrene-butadiene copolymer.

Among component (a) (mixed rubber) in item 1, (a) general-purpose rubbers include natural rubber, imprene rubber, styrene-butadiene rubber, chloroprene rubber, acrylonitrile-butadiene rubber, ethylene-propylene rubber, etc. A rubber selected from rubbers having a temperature of 20°C or less is preferably used. This general-purpose rubber is 5% of the total mixed rubber.
It is mixed with the above styrene-butadiene copolymer in an amount of ~65%, more preferably 20-50%.

As mentioned above, the component (b) (filler) weighs 0 to 100 parts by weight per 100 parts by weight of the synthetic rubber. It is necessary that the amount of Il'W is blended, and it is particularly preferable that the amount is 20 to 80 parts by weight.

Component (b) includes calcium carbonate, magnesium carbonate, barium carbonate, strontium carbonate, barium sulfate, calcium sulfate, dolomite, kaolin clay, calcined clay, hard clay, sericite, talc, talc,
Wollastonite, hennite, muscovite, phlogopite, biotite, aluminum hydroxide, zinc white, activated clay, hallosite, titanium liquefaction, stone, light ash, assembly method, diatom-1- A filler selected from non-reinforcing or weakly reinforcing fillers such as , Shirasu, and Shirasu balloons is preferably used.

] As mentioned above, component (C) (reinforcing agent) in Section 2 must be blended in an amount of 5 to 80 parts by weight per 100 parts by weight of the mixed rubber in Section 1. It is preferable that it is part b1.

Component (e) is preferably selected from reinforcing agents such as carbon black, white carbon, anhydrous silicic acid, hydrated silicic acid, synthetic silicates, and activated calcium carbonate.

As mentioned above, the component (d) (plasticizer) in ``1. Preferably.

Component (d) includes aromatic oils, naphthenic oils, spindle oils, polybutene, organic acid derivatives such as dioctyl phthalate-1, and non-alcoholic derivatives such as phosphoric acid derivatives such as phosphorus-resistant tricresyl and sulfuric acid derivatives. , anything that can normally be used for rubber can be used.

The low resilience rubber composition of the present invention comprises the above (a) to (d).
It can be obtained by adding (e) a vulcanizing agent/vulcanization accelerator to a mixture consisting of the three components, and heating and curing the mixture (119). In this case, known vulcanizing agents such as organic harsh compounds, sulfur, and organic sulfur compounds can be used. The vulcanizing agent is usually used in an amount of 0.5 to 10 parts by weight per 100 parts by weight of the mixed rubber. As the vulcanization accelerator, known ones such as aldehyde-amines, aldehyde-ammonias, dithiocarbamates, guanidines, thiurams, sulfenami Fs, thiazoles, and thioureas can be used. The vulcanization accelerator is usually used in an amount of 0.5 to 10 parts by weight per 100 parts of the mixed rubber. Furthermore, in addition to the L-named components, optional components such as one laths and anti-aging agents for preventing deterioration can be added to the low resilience rubber composition of the present invention.

The low rebound elasticity rubber composition of the present invention can be mixed and cured by heating in a conventional manner. In this case, the curing temperature is 110-1
The temperature is preferably 80°C. If the curing temperature is below 110°C, it will take a long time to cure, and if it is above 180°C, the physical properties will deteriorate.

The low-resilience rubber composition of the present invention is
It exhibits a low resilience of 0% to 30% in a wide temperature range of 0% to 30%, and as a result, it exhibits extremely non-slip properties even when wet with water, and is effective in mitigating shocks and vibrations. Furthermore, the low resilience rubber composition of the present invention has sufficient strength as a rubber grip used under severe conditions.

Although the low-rebound elastic rubber composition of the present invention can be used as is to produce rubber grips with good performance, it is possible to obtain even better performance by selecting an appropriate material for the surface shape. 11) For example, if you add a texture like sandpaper or a pattern like the surface of a tire, it will become more difficult to slip even if the book gets wet.

As described above, when the low-resilience rubber composition of the present invention is used as a material for a rubber grip, the low-resilience rubber composition of the present invention is extremely difficult to slip even when wet with water, so that when using the rubber grip, the hand does not slip. This prevents water from spilling due to slipping of hands. In addition, the low rebound elasticity rubber composition of the present invention has a strength comparable to that of ordinary rubber, so it can withstand use under harsh conditions. Furthermore, the low rebound elastic rubber composition of the present invention has impact resistance.
Because it has the effect of dampening vibrations, it is possible to make rubber grips that effectively dampen shocks and vibrations.

Examples 1 to 2, Comparative Examples 1 to 3 The present invention will be specifically explained by showing Examples below. [Examples 1 to 2, Comparative Examples 1 to 3] After kneading with rolls at a temperature of 70°C, it was formed into a sheet. After that, fill it into a suitable mold and heat it to 1
After vulcanization at 60° C. for 10 minutes, the mold was demolded.

In Table 1, calcium carbonate was used as the filler and aroma oil was used as the plasticizer. Further, in Table 1, parts are parts by weight, and % is weight %.

Next, various physical properties of Examples 1 and 2 and Comparative Examples 1 and 2 were measured. Further, for comparison, the physical properties of a commercially available rubber grip for golf clubs (Comparative Example 3) were similarly determined. The results are shown in Table 2. The hardness in Table 2 was measured at 25° C. using a type A hardness needle specified in JIS K6301, and the rebound resilience was measured at 25° C. using a Dunlop tripsometer. Further, the tensile test was performed using an Instron type tensile tester.

From the results in Table 2, the low rebound elasticity rubber composition of the present invention has sufficient strength compared to Comparative Examples 1 to 3, and has a wider range than Comparative Example 3 (commercially available rubber grip for golf clubs). It is recognized that it has low rebound properties in the temperature range.

Next, the rubber composition of Example 1 was processed into a golf club rubber grip, and a commercially available golf club rubber grip (
In comparison with Comparative Example 3), the slippage during dry and wet conditions was evaluated using a sensory test and a skin tochister. The sensory test is
100 in three levels: non-slip, normal, and easy to slip.
I evaluated it based on how people felt. In addition, a skid tester manufactured by Tanito Koki Co., Ltd. was used, and the road surface was made of concrete. The results are shown in Table 3.

From the results in Table 3, it can be seen that the low rebound elasticity rubber composition of the present invention is extremely hard to slip even when wet with water, compared to commercially available rubber grips for golf clubs.

Table 1 Table 2

Claims (1)

[Scope of Claims] 1. (a) A: High styrene-content styrene-butadiene copolymer whose styrene content is adjusted to 45 to 70% by weight by polymerization process or blending B: Based on the amount of H-silver rubber Mixed rubber of high styrene content styrene-butadiene copolymer and general purpose rubber consisting of 5 to 65% by weight of general purpose rubber (b) 0 to 100 parts by weight of filler per 100 parts by weight of mixed rubber (c) Mixed rubber 5 to 80 parts by weight 111 per 100 parts by weight
Reinforcing agent (d) Plasticizer in an amount of 0 to 60 parts by weight per 100 parts by weight of the mixed rubber (e) A mixture consisting of a vulcanizing agent and a vulcanization accelerator is heat-cured and the rebound resilience is 0 to 60 parts by weight.
30% low rebound elastic rubber composition