色综合久久久久综合99,欧美一性一交一免费看,惠民福利狂野欧美性猛交xxxx,国产美女精品人人做人人爽,国产精品人人做人人爽人人添 ,国产精品无码不卡免费视频,亚洲AV无码专区在线观看成人,产成a人亚洲精v品无码,欧美国产日韩a在线视频,扒开女人两片毛茸茸黑森林

Let's understand the nature of epoxy in epoxy tubes

Editor:浙江和泰新材料股份有限公司 │ Time:2019-11-19 

The epoxy tube is made of electrical alkali-free glass fiber cloth impregnated with epoxy resin and processed by hot pressing in a baking and molding mold. The cross section is a round rod. The glass rod has high mechanical properties. Dielectric properties and good machinability. It is suitable for use as insulation structural parts in electrical equipment, and can be used in humid environment and transformer oil.


Let us understand the nature of epoxy in epoxy tube


No matter what form of water-based epoxy resin and water-based epoxy curing agent is selected, the water-based epoxy system that has practical application value is a dispersed multi-phase structure. It consists of water-based epoxy resin, water-based epoxy curing agent, and water. Phase composition, its film-forming mechanism is different from that of ordinary polymer emulsions such as acrylic emulsions (condensation and film formation, physical process), and is not exactly the same as the film-forming of solvent-based epoxy. In solvent-based epoxy systems, Both epoxy resin and curing agent are dissolved in organic solvents in the form of molecules, and the system formed is homogeneous. The curing reaction proceeds between molecules, so the curing reaction proceeds relatively completely, and the cured product formed is also homogeneous. .


Waterborne epoxy is a multi-phase system. Epoxy resin and curing agent are dispersed in the water phase as a dispersed phase. The cross-linking and curing process is a process of internal diffusion and cross-linking between particles during the evaporation of water. The degree of epoxy curing depends on four factors:


a) Compatibility: The better the compatibility between the water-based epoxy resin and the water-based epoxy curing agent, the more favorable the internal diffusion of the curing agent particles and the epoxy resin particles, and the better the curing reaction;


b) Particle size: When the particle size is small, the particles of the dispersed phase of the water-based epoxy resin and the water-based epoxy curing agent can sufficiently penetrate into the core to achieve a more complete degree of curing;


c) Hydrophilic-lipophilic balance value: The hydrophilic-lipophilic balance values of water-based epoxy resin and water-based epoxy curing agent are close to each other, and a consistent coexisting and stable state is achieved in the water phase. If the difference is large, the hydrophilicity is stronger. The components will gradually accumulate in the aqueous phase, causing the resin phase and the curing agent phase to separate;


d) Dispersion uniformity: In the state of multi-phase separation, the resin phase and curing agent phase can be evenly distributed in the water phase only through a certain mechanical stirring effect; (Epoxy is very important to stir and mix in the application) Some friends think that in the process of using oily epoxy, it can form a film with simple stirring or even without stirring. In fact, there is a big misunderstanding, because the oily epoxy used is dissolved by solid epoxy such as 75% of E- 20, even if no curing agent is added, the solvent can form a very hard dry film after the solvent is volatilized, but this dry film is cured without cross-linking of the curing agent, and becomes liquid after heating, and the dry film has no performance at all.


久久久久久精品一区二区国产不卡| 少妇粉嫩小泬喷水视频WWW| 国产精品免费精品自在线| 国产精品99久久99久久久不卡| 免费看成人毛片无码视频| 久久综合色鬼高清无码视频| 99久久精品费精品国产一区二区| 桃美女性感视频一区二区三区| 日韩专区一中文字目一区二区| 大屁股av系列在线 哟男哟女视频八区 | 久久99r66热这里有精品| 人妻少妇精品久久久久久| 无码中文字幕AⅤ精品影| 三级片大全中文字幕| 国产AV无码一区二区三区| 国产精品国产三级在线专区| 国产真实乱子伦精品视手机观看| 91免费视频APP黄| 国产在线拍揄自揄视频不卡99| 九九精品国产亚洲AV日韩| 久久婷婷五月综合97色直播| 国产真实老熟女无套内射| 国产精品久久毛片免播| 秋霞鲁丝片Av无码少妇| 亚洲一区波多野结衣在线| 激情小说强奸乱伦亚洲色图| 国产又黄又爽又色又刺激视频| 色欲精品人妻AV一区二区三区| 四虎永久在线精品免费一区二区| 国产又爽又黄又不遮挡视频| 国产乱人伦偷精品视频| 97久久精品无码一区二区天美| 日本大胆欧美人术艺术| 日本大胆欧美人术艺术| 亚洲另类自拍丝袜第1页| 9889 精品国产一区二区三区香蕉| 亚洲欧美日韩综合俺去了| 国产一区二区在线视频| 国产三级国产经典国产AV| 国产精品美女久久久久久| 伊人久久大香线蕉综合亚洲|