| In our daily life, we could see fogging or icing phenomena, suchas the mist on the windowscreens, on the window of the bathroom, andon the plastics of the plastic greenhouse etc. As there is a difference ofthe temperature on the two separated sides, and saturated vapor tensionon the low temperature surface is lower than the one in thesurroundings, vapor begins to conglomerate on the surface of thesubject, and thus becomes fog in forms of small drops of water, whichrefract and reflect light. Such kind of fog seriously reduces thetransparence of the material, and greatly affects our sight. If thetemperature on one side is low enough to form ice, manyinconveniences and even great loss might be caused. In recent years, the progress in the study of optical resin has beenmade one after another home and abroad. New optical resin withhigh-impact strength has been developed as a substitute for glass. It ischaracterized by its low density, high-impact strength and processingflexibility, so it could be carried into execution in our daily life,transportation and national defense etc. In these resin materials,polycarbonate is carefully chosen, as it is easy to be prepared. Inaddition, its high-impact strength, high thermosetting property, thestability of its size and its self-distinguishing properties alsodistinguish itself from other materials. However, it is easy to bescratched in the process of transportation, cleaning and use.Furthermore, it couldn't inhabit fog on its surface, which directlyaffects the transparence and beauty. In order to solve these problems,people have made numerous experiments, attempting to inhabited fogand increase its abrasion resistant property. There are many patents anddocumentaries abroad involving compounds which contain acrylic IIIresin, ultra-violet solidified (methylic)acrylic ester and surfactant.These varying compounds cold provide abrasion-resistant propertywhile bearing come anti-fogging imperfections. When the substrate is polycarbonate, substrate and solidifiedcoating are hard to combine. As a result, we face a dilemma inimproving the antifogging and abrasion-resistant properties of thesecompounds and it seem impossible to come up with a means to satisfyboth. In order words, when its abrasion-resistant property is improved,it anti-fogging property gets worsened, and vice versa. A new way is put forward in a foreign patent to solve theproblems mentioned above. It suggests that we rub the resin substrateswith a layer of hydrophilic resin and the monomer, which containssilicon, then increase the temperature, and solidify in ultraviolet. In this paper, the method of polymer resin coating is adopted tosynthesize two kinds of ternary hydrophilic polymer copolymeranti-fogging dope wafting: GMA/HEMA/NVP tercopolymer andGMA/HEMA/AA tercopolymer, their anti-fogging properties are alsotested determined.Different crosslinking reagents are added into tercopolyment in orderto change the surface hardness of the PC. The results are as flows: 1. GMA/HEMA/NVP tercopolymer. (1)The PC of polymer M dope. Possesses an excellent transparentand anti-fogging properties coffer solidified, but its rigidity of thesurface and its high-impact strength are not good enough. (2)In order to improve the surface property of PC and have isanti-fogging property as well, 1% of SR205. (volume ratio) of 2.5% ofN, N-methylenebisacrylamine (quality ratio) could be added intocopolymer M. Better results will be achieved. 2. GMA/ HEMA /AA tercopolymer IV(1)All the coatings synthesized by tercopolymer N itself,N, N-methylenebisacrylamine and NVP possess good propertied ofanti-fogging, the good condition of the surface of PC, excellenttransportation and waterproof properties. (2)When a fixed quality of N, N-methylemebisacrylamine isadded into tercopolymer N, the rigidity of the surface of PC is...
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