WO2019095787A1

WO2019095787A1 - Nitrile rubber for pneumatic nail gun cushion and preparation method therefor

Info

Publication number: WO2019095787A1
Application number: PCT/CN2018/103385
Authority: WO
Inventors: 韩昶
Original assignee: 江门市鑫辉密封科技有限公司
Priority date: 2017-11-17
Filing date: 2018-08-31
Publication date: 2019-05-23
Also published as: CN107805326A

Abstract

Provided is a nitrile rubber for pneumatic nail gun cushion which is prepared by the following components in parts by weight: 95-105 parts of nitrile rubber, 2-10 parts of vulcanizing agent, 2-8 parts of zinc oxide, 1-5 parts of anti-aging agent, 40-100 parts of carbon black, 0-30 parts of plasticizer and 3-10 parts of aramid short fiber. By adding aramid short fiber to the nitrile rubber, it not only does not delay the vulcanization time, but also significantly increases the tensile strength and modulus of the rubber product, so as to improve the impact resistance of the rubber product. Therefore, the product can adapt more severe shock absorption condition, which can meet the requirements of the high impact-resistant shock absorption of the current pneumatic nail gun.

Description

Nitrile rubber for pneumatic nail gun cushion and preparation method thereof

Technical field

The invention relates to the technical field of rubber compounding and vulcanization, in particular to a preparation method of a nitrile rubber for a pneumatic nail gun cushion.

Background technique

Nitrile rubber (NBR) is prepared by emulsion polymerization of butadiene and acrylonitrile. The nitrile rubber is mainly produced by low-temperature emulsion polymerization, which has excellent oil resistance, high wear resistance and good heat resistance. Strong adhesion. The disadvantages are poor low temperature resistance, poor ozone resistance, poor insulation performance and slightly lower elasticity. NBR is widely used in the preparation of various oil-resistant rubber products, oil-resistant gaskets, gaskets, casings, flexible packaging, soft rubber hoses, printing and dyeing rubber rollers, cable rubber materials, etc., and is essential in the automotive, aerospace, petroleum, copying and other industries. Elastic material.

At present, NBR has been widely used in the shock absorption industry. Due to the increasingly stringent performance, the traditional rubber products can only meet the requirements of low shock absorption requirements, and it is difficult to meet the high frequency and high impact working conditions.

Summary of the invention

The main object of the present invention is to prepare a nitrile rubber product for a pneumatic nail gun cushion, which aims to improve the high impact damping performance of the product.

The object of the invention is achieved by the following technical solution: a nitrile rubber for a pneumatic nail gun cushion, which is made of the following parts by weight:

As a modification of the above technical solution, the vulcanizing agent is a combination of any one or more of sulfur, TMTD, CBS, and MBTS.

As an improvement of the above technical solution, the antioxidant is any one or a combination of two of the antioxidant 4010NA and the antioxidant MBZ.

As a modification of the above technical solution, the carbon black is any one or a combination of two of carbon black N550 and carbon black N774.

As a modification of the above technical solution, the plasticizer is any one of stearic acid and acetyl tributyl citrate or a combination of any two.

As an improvement of the above technical solution, the aramid staple fiber has an aspect ratio of 30 to 80.

The invention also discloses a preparation method of a nitrile rubber for a pneumatic nail gun cushion, comprising the following steps:

Step 1: Weigh each component according to the parts by weight in the formula;

Step 2: mixing the nitrile rubber, the zinc oxide, the antioxidant, the carbon black, the plasticizer and the aramid short fiber by a rubber internal mixer to obtain a rubber compound without a vulcanizing agent;

Step 3: adding the vulcanizing agent to the open vulcanizer without adding a vulcanizing agent obtained in the second step to obtain a vulcanizing agent-containing mixing rubber;

Step 4: processing the vulcanizing agent-containing rubber compound obtained in the third step into a rubber rubber embryo required for molding the product through a preforming machine;

Step 5: The rubber rubber obtained in the fourth step is vulcanized on a flat vulcanizing machine through a mold to obtain a nitrile rubber for a pneumatic nail gun cushion.

As an improvement of the above technical solution, the fourth step further comprises: pre-forming the vulcanized rubber containing the vulcanizing agent into the rubber of the desired shape before the molding.

As an improvement of the above technical solution, in step 5: the temperature controlled by the vulcanization process is 160 ° C - 190 ° C, and the time is 300 seconds - 900 seconds.

Compared with the prior art, the beneficial effects obtained by the invention are:

The technical proposal of the invention improves the fixing strength and modulus of the rubber product by adding the aramid short fiber in the formula of the nitrile rubber without delaying the vulcanization time, and the addition of the aramid short fiber in the formula The high impact resistance of rubber products enables the product to adapt to more severe shock absorption conditions, which can meet the high impact shock absorption of current pneumatic nail guns.

Detailed ways

The present invention will be further described in detail below with reference to the embodiments, but the embodiments of the present invention are not limited thereto.

The examples and comparative examples were prepared according to the following methods. The components of the examples and comparative examples are shown in the following table, and the experimental results are shown in the following table:

(1) Preparation method of rubber compounding rubber:

Step 1: Each component was weighed according to the parts by weight of the formulation in the following table.

Step 2: mixing the nitrile rubber, the zinc oxide, the antioxidant, the carbon black, the plasticizer and the aramid short fiber by a rubber internal mixer to obtain a rubber compound without a vulcanizing agent.

Specifically, start the internal mixer, put in nitrile rubber, mix for 20 to 120 seconds, and then add zinc oxide, anti-aging agent, carbon black, plasticizer and aramid short fiber, and knead for 60 to 240 seconds. The chamber is further mixed to 90 ° C to 140 ° C, and the rubber is discharged to the lower part of the mill to obtain a rubber compound without a vulcanizing agent.

Step 3: adding a vulcanizing agent to the mill without adding a vulcanizing agent to obtain a vulcanizing agent-containing compound.

Specifically, the cold film is first heated by an open mill, and then a smooth wrap rubber is formed on the open mill, and a vulcanizing agent is added. After the vulcanizing agent is all added to the rubber, the film is thinned and the vulcanized product is obtained. Mixture of the agent.

Step 4: The vulcanizing agent-containing rubber compound is processed into a rubber rubber embryo required for the molded product by a preforming machine.

Specifically, the rubber compound is preheated and rolled in an open mill, the temperature of the coil is controlled at 60-90 ° C, and the rolled rubber is loaded into the preforming machine, and the temperature of the preforming machine is adjusted according to actual conditions. Pressure, a rubber latex with a weight controlled by the process.

Step 5: The rubber rubber blank is vulcanized on a flat vulcanizing machine through a mold to obtain a nitrile rubber for a pneumatic nail gun cushion.

Specifically, the rubber rubber blank is placed in a mold cavity, and is vulcanized by pressure to obtain a desired product. The vulcanization temperature is controlled at 160 ° C to 190 ° C, and the vulcanization time is controlled at 300 seconds to 900 seconds.

(2) Preparation method of test piece and sample:

The sample was vulcanized at 177 ° C for 6 minutes on a 50 ton flat vulcanizer.

(3) Pre-formed by a preforming machine, produced in an 18-cavity mold at 165 ° C * 500 s, and the product is secondarily vulcanized at 150 ° C * 0.5 h.

Examples and comparative examples (unit: parts by mass)

N3345C in the table is nitrile rubber N3345C;

The microcrystalline wax in the table is used as a processing aid for nitrile rubber, and does not affect the experimental results.

The data is analyzed to further illustrate the advantages of the present invention. From the data in the above table can be seen:

Compared with 11# and 5#, 1# does not add aramid staple fiber, and 5# adds 5 parts of aramid staple fiber. From the perspective of life, 5# can impact 320,000 times before it breaks, meeting the actual use requirements, and 1 #There is no addition of aramid staple fiber, and there has been a large damage after impacting 10,000 times. This is because the addition of aramid staple fiber significantly improves the tensile strength and impact resistance of the material, greatly improving the service life of the product.

22#, 3#, 4#, 5#, 6# comparison, although both 2# and 3# have added aramid short fibers, but the amount of 2# is not enough, the material performance is limited, and the requirements for use are not met; 3# If the amount is too large, the material has a high tensile strength, but the elongation of the material is too low, and the relatively large deformation cannot be withstood, so the service life is not satisfactory. From the data point of view, it is desirable to select 3 to 10 parts of aramid short fibers.

3 From all the data, the other role of adding aramid staple fiber is to reduce the heat generation of the product during the work process. At this level, increasing the amount of aramid staple fiber can increase the life of the product, but the product ultimately The service life is the result of the combined effects of the material's tensile strength, modulus, elongation, and heat generation. As the amount of aramid staple fiber increases, the heat generation tends to decrease, and the elongation also decreases. When the elongation decreases to a certain extent, the shapeable variable is too low, which is not conducive to product performance. Comprehensive manifestation.

Compared with the prior art, the technical solution of the present invention does not delay the vulcanization time by adding the aramid staple fiber in the formulation of the nitrile rubber, and the modulus of the rubber product is greatly increased after the addition of the aramid staple fiber in the formulation. Compared with the traditional formula, the rubber product has greatly increased the high impact resistance of the rubber product, and expanded the use condition of the product, so that the product can adapt to the more severe environment of the shock absorption requirement, and can meet the high resistance of the current pneumatic nail gun. Use for shock absorption.

The above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other embodiments may be made based on the above description. It is to be understood that various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims

A nitrile rubber for a pneumatic nail gun cushion, characterized in that the nitrile rubber is made of the following parts by weight:
A nitrile rubber for a pneumatic nail gun cushion according to claim 1, wherein the vulcanizing agent is a combination of any one or more of sulfur, TMTD, CBS and MBTS.
A nitrile rubber for a pneumatic nail gun cushion according to claim 1, wherein the antioxidant is any one or a combination of two of an antioxidant 4010NA and an antioxidant MBZ.
A nitrile rubber for a pneumatic nail gun cushion according to claim 1, wherein the carbon black is any one or a combination of carbon black N550 and carbon black N774.
The nitrile rubber for a pneumatic nail gun cushion according to claim 1, wherein the plasticizer is any one or two of stearic acid and acetyl tributyl citrate. Combination of people.
The nitrile rubber for a pneumatic nail gun cushion according to claim 1, wherein the aramid staple fiber has an aspect ratio of 30 to 80.
The invention relates to a method for preparing a nitrile rubber for a pneumatic nail gun cushion, which comprises the following steps:

Step 1: Weigh each component according to the parts by weight in the formula;

Step 2: mixing the nitrile rubber, the zinc oxide, the antioxidant, the carbon black, the plasticizer and the aramid short fiber by a rubber internal mixer to obtain a rubber compound without a vulcanizing agent;

Step 3: adding the vulcanizing agent to the open vulcanizer without adding a vulcanizing agent obtained in the second step to obtain a vulcanizing agent-containing mixing rubber;

Step 4: processing the vulcanizing agent-containing rubber compound obtained in the third step into a rubber rubber embryo required for molding the product through a preforming machine;

Step 5: The rubber rubber obtained in the fourth step is vulcanized on a flat vulcanizing machine through a mold to obtain a nitrile rubber for a pneumatic nail gun cushion.
The method for preparing a nitrile rubber for a pneumatic nail gun cushion according to claim 7, wherein in the step 5, the temperature controlled by the vulcanization process is 160 ° C - 190 ° C, and the time is 300 seconds. -900 seconds.