双组分聚氨酯道桥密封膏的研制

以聚醚多元醇、甲苯二异氰酸酯(TDI)、扩链剂、填料、复合催化剂、增塑剂、触变剂为主要原料,制备了一种低模量、高弹性、高粘接力的双组分聚氨酯道桥密封膏,讨论了影响该密封膏性能的因素。结果表明,当异氰酸酯指数在1.0~1.35、复合催化剂用量在0.9%~1.1%、触变剂用量为10%~12%、活性轻钙用量为18%~21%时,制备的密封膏的拉伸模量、下垂度、可施工时间、表干时间、弹性等性能较佳。同时通过采用自制的复合催化剂体系,利用化学增稠的方法解决了搅拌速度低对生产设备带来的问题,获得了性能优异的产品。     

新型汽车折边胶的研制

用环氧树脂、纳米橡胶改性环氧树脂、双氰胺、促进剂、PVC糊树脂、填料、触变剂等制备出一种汽车用环氧折边胶。研究了促进剂、纳米橡胶改性环氧树脂、填料对折边胶性能的影响。实验结果表明,当促进剂4,4’-亚甲基-二(苯基二甲基脲)为环氧树脂质量的1%,纳米橡胶改性环氧树脂MX-125为树脂质量的60%,硅微粉为树脂质量的50%时,折边胶综合性能最佳。     

水泥基腻子面漆二合一内墙涂料的制备

以自制的可再分散乳胶为主要成膜物质,结合水泥水硬性无机粘结剂制备了腻子面漆二合一内墙涂料,重点讨论了可再分散乳胶粉、纤维素醚、粉状憎水剂对涂膜性能的影响.实验结果表明,可再分散乳胶粉及其用量对腻子面漆二合一涂料性能具有重要影响,当其用量为4%～6%时,涂膜具有良好的综合性能;纤维素醚能明显改善涂料的施工性能和保水性能,其最佳用量为0.3%;粉状憎水剂显著提高涂膜的耐水性和耐洗擦性能,其用量为0.3%时可达到很好的效果.产品综合性能达到或超过国标JG/3049-1998N型和GB/T 9756-2001优等品指标值.     

可再分散乳胶粉型耐水腻子的制备及耐水机理

用自制丙烯酸酯乳液喷雾干燥制得的可再分散乳胶粉制备了性能优良的耐水型腻子。讨论了可再分散乳胶粉用量、水泥用量、纤维素醚用量对腻子粘结强度、耐水性以及施工等性能的影响,确定了最佳用量。实验结果表明：可再分散乳胶粉用量为3%-4%,水泥用量25%-30%,纤维素醚用量为0.4%-0.6%时,配制的腻子粘结强度高、耐水性好且施工容易,满足工程应用要求。同时对腻子体系的耐水作用机理进行了探讨。     

填料助剂对MDI型聚氨酯弹性体复合材料性能的影响

采用一步法制备有机微球/二氧化硅/MDI型聚氨酯弹性体复合材料,研究了触变剂和填料表面处理剂对复合材料性能的影响。研究表明,触变剂BYK-410用量为0.5%时,材料的力学性能较好,试片正反面的硬度差和表面电阻率差值较小,体积电阻率较大,但混合后树脂的初始黏度最大;铝酸酯偶联剂改性的二氧化硅分散较均匀,材料的力学性能、电阻率和动态力学性能均较好,有机硅偶联剂的改性效果较差。     

水性不饱和聚酯腻子的研究

以含水不饱和聚酯树脂为基料,配合去离子水、促进剂、润湿分散剂、抗收缩剂、触变剂、填料等研制出水性不饱和聚酯腻子。研究了含水不饱和聚酯树脂、去离子水以及助剂配比对水性不饱和聚酯腻子性能的影响,并确定了制备水性不饱和聚酯腻子的基本条件。     

巴士客车用丙烯酸聚氨酯罩光清漆的制备

介绍了以聚酯树脂和特种助剂对罩光清漆进行改性,制得了适合巴士客车使用的丙烯酸聚氨酯罩光清漆。分析了聚酯树脂和特种助剂对罩光清漆的丰满度、抗划伤性能、流平性和施工性能的影响。结果表明当选用高固含、高羟基聚酯树脂对丙烯酸树脂进行改性时,涂料具有较好的丰满度和抗划伤性能;当流平剂选用丙烯酸类和有机硅类搭配使用时,可大大提高罩光清漆的流平性能;当触变剂BYK-410的用量为0.3%时,清漆一次涂装干膜60μm不流挂,当DBE慢干剂用量为2%时,涂料具有好的施工性能。     

触变剂对桥梁加固用环氧树脂胶粘剂的影响研究

正以触变剂掺量为参数,考察了其对环氧树脂胶粘剂的施工工艺性(黏度、触变指数)及力学性能(钢对钢拉伸剪切强度、拉伸强度及断裂伸长率)的影响。结果表明:适当的触变剂掺量不仅能改善环氧树脂胶粘剂的施工性能,而且对其粘接性能和胶体性能也具有调节作用。当触变剂为2%时,环氧树脂胶粘剂的黏度较低,有利于施工搅拌;当触变剂为3%时,触变指数相对最大。随着触变剂掺量的增大,环     

顺酐化豆油改性不饱和聚酯树脂腻子的制备

以顺酐化豆油及油酸封端对腻子专用UPR进行改性,采用三步加料逐步升温催化熔聚法,研究了从多元醇、酸体系及其醇过量、顺酐化豆油的用量、油酸封端比例对UPR性能的影响。试验发现利用顺酐化豆油的用量为11.53%,采用5%的油酸进行封端时,醇过量为12.24%~15.15%,合成的UPR性能较好,其中14.94%为最佳的醇过量值,得到的新型金属腻子专用树脂性能优良。并探索调整一套适用于新型腻子树脂的填料体系,制得一种环保型的金属腻子。     

WFZ-151粉末腻子的性能研究

以粉煤灰、重质碳酸钙为填料,乳胶粉、水泥为粘结料,配以适当的粉状助剂及其他辅料,制得了一种粉末腻子;探讨了乳胶粉、水泥、粉煤灰、纤维素醚的用量对粉末腻子性能的影响;测试了粉末腻子的理化性能。研究结果表明,所配制的粉末腻子是一种具有优良理化性能和施工性能的环保性腻子。     

焦油一次汽化温度计算方法的探讨

利用相平衡原理得出的焦油蒸馏时一次汽化温度的计算方法,其结果与按经验公式的计算结果进行了比较,同时讨论了一次汽化温度与焦油馏分产率及二段蒸发器过热蒸汽用量的关系。     

Techniques for screening adhesives for structural applications

—Due to its chemistry, no structural adhesive system (epoxies, acrylics, etc.) is likely to offer an ideal combination of toughness, strength, moisture resistance, and ambient-temperature curing. Therefore, for effective use of adhesives in primary structures, an engineer must be able to identify adhesives that represent an optimum compromise among the different properties. In this paper, we present techniques for screening high-strength, ambient-temperature-curing adhesives for (1) moisture resistance under sustained loading and (2) fracture resistance in a way that is directly related to joint performance.     

Efficacy for Whitlockite for Augmenting Spinal Fusion

Whitlockite (WH) is the second most abundant inorganic component of human bone, accounting for approximately 25% of bone tissue. This study investigated the role of WH in bone remodeling and formation in a mouse spinal fusion model. Specifically, morphology and composition analysis, tests of porosity and surface area, thermogravimetric analysis, an ion-release test, and a cell viability test were conducted to analyze the properties of bone substitutes. The MagOss group received WH, Group A received 100% beta-tricalcium phosphate (β-TCP), Group B received 100% hydroxyapatite (HAp), Group C received 30% HAp/70% β-TCP, and Group D received 60% HAp/40% β-TCP (n = 10 each). All mice were sacrificed 6 weeks after implantation, and micro-CT, hematoxylin and eosin (HE) staining, and Masson trichome (MT) staining and immunohistochemistry were performed. The MagOss group showed more homogeneous and smaller grains, and nanopores (<500 nm) were found in only the MagOss group. On micro-CT, the MagOss group showed larger fusion mass and better graft incorporation into the decorticate mouse spine than other groups. In the in vivo experiment with HE staining, the MagOss group showed the highest new bone area (mean: decortication group, 9.50%; A, 15.08%; B, 15.70%; C, 14.76%; D, 14.70%; MagOss, 22.69%; p < 0.0001). In MT staining, the MagOss group demonstrated the highest new bone area (mean: decortication group, 15.62%; A, 21.41%; B, 22.86%; C, 23.07%; D, 22.47%; MagOss, 26.29%; p < 0.0001). In an immunohistochemical analysis for osteocalcin, osteopontin, and CD31, the MagOss group showed a higher positive area than other groups. WH showed comparable bone conductivity to HAp and β-TCP and increased new bone formation. WH is likely to be used as an improved bone substitute with better bone conductivity than HAp and β-TCP.     

Demand Increases for New Fungicides for Rice

<正> After June this year China's regions growingmiddle and late rice had widespread blastand sheath/culm blight.Such diseasesplagued 19.2 million hectares.Starting fromJuly the market for new fungicides that cancontrol blast and sheath/culm blight for ricewas more and more active.Makers of traditional pesticides for thecontrol of blast have to contend with fiercecompetition from new pesticides in marketthis year.Kitazine,iprobenfos,isoprothiolane and tricyclazole,oftenused by farmers in the past,are graduallybeing replaced by new varieties with high