插插无码视频大全不卡网站-中文亚洲av片不卡在线观看-在线高清理伦片a-自愉自愉产区二十四区

2021-8-4

Do you know how the color of silicone products comes from?

Many consumers are attracted by the color and appearance of some products, especially in gifts and handicrafts. As we all know, silica gel products are a kind of rubber and plastic products that ar..

2021-8-4

Basic introduction of silica gel materials

Silica gel is a highly active adsorption material, which is an amorphous material. It contains polysiloxane, silicone oil, silica (silica), coupling agent and filler. The main component is silica, ..

2021-8-4

Silicone earphone cover tells you how to clean it

Method 1. When there is a small part of dust on the silicone earphone cover after going out, you can simply wash it with clean water to remove the dust.
Method 2. When the silicone earphone ..

2021-8-4

What is the difference between silicone gel and silicone rubber?

A lot of friends know that silicone rubber products have a certain strength category. Although it looks soft, it can not reach the standard beyond certain hardness and softness. For example, too ha..

2021-8-4

Introduction to rubber parts manufacturers rubber aging

The preparation of rubber raw materials can be divided into three basic processes:
1. Plasticizing: plasticizing is to cut the raw rubber, plasticize and homogenize the raw rubber, and help ..

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