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.


久久精品国产99精品国产亚洲性色| 亚洲国产精品一区二区第四页| 精品无码国产自产在线观看极品| 秋霞电影午夜无码免费视频| ?愛妃?国产一区二区三区视频精品| 久久亚洲AV成人无码动态图| 国产在线综合一区二区三区| 国产在线无码精品麻豆不卡| 国内野外强奷在线视频| 久久精品噜噜噜成人AV | 国产成人精品视频a片西瓜视频| 国产亚洲人成网站在线观看| 久久久久成亚洲国产av| 老子午夜精品888无码不卡| 免费午夜伦费影视在线观看| 99在线精品免费视频九九视| 亚洲综合AV在线在线播放| 久久久久久久久毛片精品| 欧美日本一区二区欧美专区一区| 成人国内免费精品视频在线观看| 中文有码无码人妻在线| 精品国产自在在线午夜| 无码视频痴汉在线观看| 青草视频在线播放| 精品国产AⅤ一区二区三区4区| 午夜国产精品理论片久久影院| 国产精品亚洲一区二区三区久久| 99久久精品自在自看国产| 国产初高中生真实在线视频| 亚洲熟妇无码一区二区三区导航| 视频一区二区美女引诱| 中文有码无码人妻在线| 午夜香吻免费观看视频在线播放| 国产精品亚洲综合色区| 日韩AV一区二区三区免费看| 国产综合视频在线观看| 午夜电影理论片费看禁忌| 欧美人与动牲交a免费观看| 久热中文字幕在线精品首页| 免费人成黄页在线观看视频国产| 久久久不卡国产精品一区二区|