阅读说明：本技术 一种高硬度高流动性的聚醚型聚氨酯混炼胶 (High-hardness high-fluidity polyether polyurethane rubber compound ) 是由 禤文权 邹明清 黎艳飞 黄律生 区志敏 于 2020-07-16 设计创作，主要内容包括：本发明公开了一种高硬度高流动性的聚醚型聚氨酯混炼胶,所述混炼胶包括：100质量份聚氨酯生胶UR101；30～50质量份沉淀法白炭黑；0.5～1质量份硬脂酸；1～3质量份硅烷偶联剂；10～18质量份防焦烧型TMPTMA；1～2质量份交联助剂ZDMA；2～5质量份防焦烧型过氧化物硫化剂；0～4质量份加工助剂。本发明采用聚醚型聚氨酯生胶UR101生胶作为主体材料,选用一些相容性好的配合剂,使混炼胶满足高硬度要求的同时,门尼粘度控制在50以下,并且能延长焦烧时间满足加工工艺要求,最终使混炼胶满足高硬度高流动性的性能要求。(The invention discloses a high-hardness high-fluidity polyether polyurethane rubber compound, which comprises the following components in percentage by weight: 100 parts by mass of polyurethane raw rubber UR 101; 30-50 parts by mass of precipitated silica; 0.5 to 1 part by mass of stearic acid; 1-3 parts by mass of a silane coupling agent; 10-18 parts by mass of scorch-proof TMPTMA; 1-2 parts by mass of a crosslinking assistant ZDMA; 2-5 parts by mass of an anti-scorching peroxide vulcanizing agent; 0-4 parts by mass of a processing aid. According to the invention, polyether polyurethane crude rubber UR101 crude rubber is adopted as a main material, and some compounding agents with good compatibility are selected, so that the Mooney viscosity is controlled below 50 while the rubber compound meets the requirement of high hardness, the scorching time can be prolonged to meet the requirement of a processing process, and finally the rubber compound meets the performance requirement of high hardness and high fluidity.)

1. A polyether polyurethane gross rubber with high hardness and high fluidity is characterized in that: the formula of the rubber compound comprises the following components:

100 parts by mass of polyether polyurethane raw rubber UR101

30-50 parts by mass of precipitated silica

0.5 to 1 part by mass of stearic acid

1-3 parts by mass of a silane coupling agent

10-18 parts by mass of scorch-proof TMPTMA

1-2 parts by mass of crosslinking assistant ZDMA

2-5 parts by mass of scorch-resistant peroxide vulcanizing agent

0-4 parts by mass of processing aid

A rubber composition according to claim 1, wherein: the hardness of the rubber compound is from 90 degrees to 95 degrees Shore A.

2. A rubber composition according to claim 1, wherein the rubber composition has a Mooney viscosity (ML) at 100 ℃ in the macrorotor

3. A rubber composition according to claim 1, wherein: the sulfur-dependent transsulfuration performance (MDR) of the rubber compound is detected by a rotor-free sulfur-dependent analyzer at 175 ℃ for 15 minutes, and the scorch time (ts2) is more than 30 seconds.

Technical Field

The invention relates to a polyurethane rubber compound technology, in particular to a polyether polyurethane rubber compound with high hardness and high fluidity.

Background

It is well known that polyurethane rubber is the best wear resistant among all rubbers, and is called "wear resistant rubber". The polyurethane rubber compound prepared by taking the polyether polyurethane rubber as the main body has high elasticity and mechanical strength, excellent oil resistance, water resistance and ozone aging resistance, good heat resistance, low temperature resistance and processing stability and wide hardness range besides excellent wear resistance, and can be prepared into materials from 25A to 95A through different rubber compound formulas. Therefore, the polyurethane rubber compound is widely applied to the fields of equipment, electric appliances, automobiles, textiles, shoe making and the like, and is suitable for being made into various high-performance sealing elements, O-shaped rings, rubber tubes, driving belts, rubber rollers, shock absorbers, high-load gear boxes, soles, antistatic products, various molded products and the like.

The high hardness in the rubber compound is generally not less than Shore A85 degrees. High hardness rubber compounds are generally achieved by adding a large amount of reinforcing agent, but too much reinforcing agent may cause some process problems: firstly, the dispersion uniformity of the mixing rubber is deteriorated, and the physical properties are fluctuated; secondly, the Mooney viscosity of the rubber compound is increased, and the flowability of the rubber compound is deteriorated; further, the internal heat of the rubber compound becomes larger, the scorch time is shortened, the rubber material is easily scorched during the mixing, and the fluidity is deteriorated during the vulcanization. Due to these process problems, the use of high hardness compounds is somewhat limited. For example, some molded products with large size and complex shape have poor flowability and short scorching time, so that the mold cavity cannot be filled with the sizing material during molding, and the sizing material has poor air exhaust, thereby causing product quality defects (such as glue shortage, poor edge tearing due to thick rough edges, air collapse, dimensional deviation and the like). Therefore, it is of great importance to improve the compound flowability of high-hardness compounds.

The way of improving the fluidity of the high-hardness rubber compound is mainly considered from two aspects, firstly, the use amount of the reinforcing agent is reduced, the Mooney viscosity of the rubber compound is reduced, but the hardness of the rubber compound is reduced by reducing the reinforcing agent, and in order to ensure that the hardness requirement is met, the purpose of improving the cross-linking density of the rubber compound by adopting the cross-linking assistant is achieved. And secondly, a vulcanizing agent and a crosslinking assistant with delayed scorch type are adopted, so that the scorch time is prolonged, and the flowability of the rubber material is improved. By combining the two measures, the fluidity of the rubber compound can be greatly improved, and the requirement of high-hardness molded products on the fluidity of rubber compounds can be met.

Disclosure of Invention

The invention aims to provide a high-hardness high-fluidity polyether polyurethane rubber compound to meet the requirement of a high-hardness product on the fluidity of rubber.

In order to achieve the purpose, a large number of tests are carried out, and researches show that in a polyether polyurethane rubber compound, a cross-linking aid trimethylolpropane trimethacrylate (TMPTMA) and zinc methacrylate (ZDMA) can generate a good synergistic effect, so that the hardness is greatly improved, the Mooney viscosity is greatly reduced, and when the scorch-proof TMPTMA is adopted, the scorch time can be obviously prolonged, and the flow processing of rubber materials is facilitated. The invention provides a high-hardness high-fluidity polyether polyurethane rubber compound, which comprises the following components in percentage by weight: 100 parts by mass of polyether polyurethane crude rubber UR 101; 30-50 parts by mass of precipitated silica; 0.5 to 1 part by mass of stearic acid; 1-3 parts by mass of a silane coupling agent; 10-18 parts by mass of scorch-proof TMPTMA; 1-2 parts by mass of a crosslinking assistant ZDMA; 2-5 parts by mass of an anti-scorching peroxide vulcanizing agent; 0-4 parts by mass of a processing aid.

The precipitated silica is a precipitated silica with good reinforcing property and good compatibility, such as Sil-233.

The silane coupling agent is selected mainly for coupling the organic polymer and the inorganic filler to enhance the adhesion, such as A-172.

The scorch-retarding peroxide curing agent is a scorch-retarding curing agent suitable for polyurethane rubbers, such as DCP-40 SD.

The processing aid is an optionally added aid such as an internal mold release agent, a dispersant, a colorant, and the like.

The polyurethane rubber compound has the outstanding advantages that:

1. the Mooney viscosity of the rubber compound is relatively low, and the Mooney viscosity (ML) of a large rotor at 100 DEG C) Below 50.

2. The hardness of the rubber compound can be 90A to 95A, and the requirement of high hardness of products is met.

3. The rubber material has good scorching resistance, and the scorching time (ts2) is more than 30 seconds after the sulfur change performance (MDR) is detected and the detection is carried out for 15 minutes by a non-rotor sulfur change instrument at 175 ℃.

4. The sizing material can be natural color (translucent) or be blended into other colors, and meets the color requirements of various products.

5. The comparison between the examples and the comparative examples proves that the high-hardness rubber compound has obvious advantages in rubber material fluidity and improved rubber material performance, and the performance test results of the examples and the comparative examples are detailed in table 1.

Detailed Description

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