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91.
Thermodynamic calculations were performed using a modified solgasmix-pv computer program in order to study the feasibility of codepositing boron nitride (BN) plus aluminum nitride (AIN) by chemical vapor deposition. Reactants considered were AICl3, BCl3 or B2H6, NH3, and H2. Deposition diagrams were generated for the BCl3-AICl3-NH3 system over a range of processing conditions such as temperature, total system pressure, and reagent concentrations. Codeposition of BN + AIN was predicted by the calculations for temperatures in the range of 900 to 1700 K and pressures of 10.13 to 101.3 kPa. The predicted deposition efficiency at equilibrium was much higher for BN than for AlN at most reagent compositions. The AlN deposition efficiency increased with decreasing temperature and decreasing BCl3 content, with increasing NH3 content, or with the addition of H2. Aluminum chlorides were found to be the dominant gaseous species.  相似文献   
92.
核工业专用橡胶型可剥掩蔽涂料的研制和应用   总被引:5,自引:0,他引:5  
介绍了核电、核能工业专用橡胶型可剥掩蔽涂料的研制和应用,选用新型含有苯基的聚丁二烯弹性体为基料,加入耐酸、耐辐照的颜填料和防黏剂、偶联剂及N-13a固化剂配成JF系列常温固化的核电、核能工业专用橡胶型可剥掩蔽涂料,该涂料耐酸碱、耐辐照,防污性能优良。  相似文献   
93.
研究了双组分室温固化型低表面能氟涂层的配合技术,所用材料的物化特性;讨论了基料、填料、助剂等对氟涂料的影响机理。实验结果表明:氟涂层的表面能为10.6 mJ/m2,疏水角可达到122°,附着力为1级、硬度为4H,同时涂层具有耐腐蚀和耐化学性等性质。  相似文献   
94.
纯聚酯户外消光粉末涂料的制备   总被引:4,自引:1,他引:4  
以高黏度、低酸值的含羧基饱和聚酯树脂为基料,以含有缩水甘油基的丙烯酸树脂为消光固化剂制备纯聚酯户外消光粉末涂料。介绍了该涂料的制备工艺,并讨论了原材料和生产条件对产品性能的影响。  相似文献   
95.
介绍了增塑剂的迁移性对涂层性能的影响,讨论了如何降低增塑剂的用量。  相似文献   
96.
水基含铝耐高温防腐蚀涂料   总被引:2,自引:0,他引:2  
以水溶性的磷酸盐为主要成膜物质,铬酸(盐、酐等)为调节剂,球形铝粉为颜料合成了水基含铝耐高温防腐蚀涂料,该涂料具有优异的耐热、耐湿、耐盐雾、耐高低温冲击等性能。  相似文献   
97.
Investigations have been carried out on properties of coatings, differing by their pigmentation and binder, and applied on different chemical pre-treatments of the steel surface. Paints based on alkyd and alkyd-melamine binders, pigmented with zinc phosphate and modified basic zinc phosphate were applied on amorphous and crystalline phosphated steel surface and, for the comparison purpose, on degreased steel surface. The effect of the binder, the pigment and the pre-treatment of the steel surface on the protective properties of the coatings were determined by measurements of adhesion, water absorption and water permeability and by results obtained in salt spray and Prohesion tests. Coatings based on alkyd binder show a lower damage degree and good retention of adhesion in corrosion conditions, in spite of a higher water absorption and water permeability and a lower initial adhesive strength. Protective properties of coatings have been found to be highly dependent upon the substrate pre-treatment. Chemical pre-treatment of the steel substrate increases the protective properties of the system, which is particularly evident in the case of crystalline phosphating and the coating pigmented with modified basic zinc phosphate. This phenomenon can be explained by the synergism between this phosphate pigment with crystalline phosphate layer.  相似文献   
98.
PP塑料底材处理剂的研制及应用   总被引:1,自引:0,他引:1  
以氯化聚丙烯为主要原料,制备了一种环保型的聚丙烯塑料底材表面处理剂。讨论了树脂基料、溶剂、乳化剂的选取及配比等因素对涂层附着力的影响,确定了处理剂的最佳配方。经试验测试,聚丙烯塑料表面经处理剂处理后,其涂层的附着力显著提高。  相似文献   
99.
简述了抗静电粉末涂料的制备机理及铝粉、氧化镁、二氧化钛和抗静电助剂添加量对涂料性能的影响,并简述其应用。  相似文献   
100.
Scanning probe microscopy (SPM) is in a period of rapid development. It shows great promise for characterizing coating surfaces. This paper describes modification of an SPM so that it can be used to mar the surfaces of coatings under controlled conditions and to characterize the mars. Mar resistance of coatings is analyzed in terms of a ‘three response, two mechanism model.' The three responses (fracture, elastic, and plastic) can be measured quantitatively using the SPM. Of the three responses, only two (fracture and plastic deformation) are marring mechanisms – elastic deformations recover instantaneously. In some cases mars resulting from plastic deformation may recover slowly with time or with immersion in water; this phenomenon is attributed to viscoelastic creep. Microhardness is also measured with the modified SPM. Some thermoset coatings appear to be substantially harder near their surfaces than in the mass of material, and such materials may respond quite differently to stress applied at different levels near the surface. This finding has important implications for all coating properties that are strongly influenced by the surface. A quantity called ‘micro mar resistance' is defined. It may be useful for comparing different coatings under specified conditions of marring. However, there can be no single quantity that expresses ‘mar resistance' of a coating under all conditions.  相似文献   
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