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贴合是橡胶加工中常用的一种工艺方法,贴合是指胶片的贴合,即使用压延机将两层或两层以上的多层的、同种或异种胶片压合在一起,使之成为较厚的胶片这样一种压延工艺过程。贴合工艺主要用于生产含胶率高、气体不易排出、气密性要求比较严格等性能要求的胶片的制备;适用于两种不同胶料组成的胶片以及夹布胶片等。在贴合胶片的生产中,为了保证贴合胶片的质量,要求各被贴胶片具有一致的可塑性,否则,将会导致胶层和起皱等现象。当胶料的配方和一次胶片的厚度均不相同时,两层胶片的贴舍,最好采用“同时贴合法”进行贴合加工,即将从压延机出来的两块新胶片同时进行热贴合。这样,可使贴合的半成品胶片致密、无气泡,也不容易起皱。 相似文献
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TREVIO Lucia CONTRERAS-ESQUIVEL Juan C. RODRíGUEZ-HERRERA Raul AGUILAR Cristóbal Noé 《Journal of Zhejiang University. Science. B》2007,(10)
The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyurethane matrices were used as the support: continuous, semi-discontinuous and discontinuous. The highest tannase production at 2479.59 U/L during the first 12 h of culture was obtained using the discontinuous matrix. The gallic acid was accumulated at 7.64 g/L at the discontinuous matrix. The results show that the discontinuous matrix of polyurethane is better for tannase production and gallic acid accumulation in a solid state culture bioprocess than the continuous and semi-discontinuous matrices. 相似文献
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:本文合成了溶剂型单组分PU胶粘剂 ,考察了聚酯多元醇的品种、分子量以及PU的分子量等对胶粘剂性能的影响 ,结果表明 :聚酯软段的结构对胶粘剂的性能影响较大。提高聚氨酯的结晶度可以增大其粘接性能 ,特别是初始粘接性能。 相似文献
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本文应用本体聚合的方法合成了一种聚氨酯(PU)胶粘剂,采用正交实验方法考察了2,4-甲苯二异氰酸酯(TDI)中的异氰酸根与聚酯多元醇(PBA)中的羟基摩尔比、扩链剂1,4-丁二醇(BDO)与聚酯多元醇(PBA)的摩尔比、催化剂的用量对聚氨酯胶粘剂剥离强度的影响,从中优化出最佳反应条件。研究发现,当n(-NCO)/n(-OH)=2,BDO/PBA=0.4,催化剂的用量为PBA的0.005%时,合成的胶粘剂性能较佳。此外,探讨了丙烯酸酯类改性聚氨酯胶粘剂,发现当甲基丙烯酸羟乙酯(HEMA)为15%(占PU量),甲基丙烯酸甲酯(MMA)为15%和偶氮二异丁腈(AIBN)为0.3%时,胶粘剂的粘接强度得到较好的提高。 相似文献
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俞丽珍 《常熟理工学院学报》2005,19(4):47-50,81
由于禁止使用CFC—11,所以原有的聚氨酯发泡系统必须被替代,但是对于冰箱和冷柜隔热用聚氨酯系统的选择涉及诸多因素,因此并不是一个简单的过程。本文阐述了卤化物发泡剂和碳氢化合物发泡剂的特性以及它们的发泡体系的物理性能,根据各种发泡体系的综合比较,环戊烷/异戊烷混合发泡体系是较理想的替代方案,目前众多冰箱、冰柜厂家已部分采用这种发泡体系,江苏白雪电器股份有限公司也将选用这一发泡体系。 相似文献
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Trevino L Contreras-Esquivel JC Rodríguez-Herrera R Aguilar CN 《Journal of Zhejiang University. Science. B》2007,8(10):771-776
The influence of the physical structure of polyurethane matrix as a support in a solid state culture in tannase production
and gallic acid accumulation by Aspergillus niger Aa-20 was evaluated. Three different polyurethane matrices were used as the support: continuous, semi-discontinuous and discontinuous.
The highest tannase production at 2479.59 U/L during the first 12 h of culture was obtained using the discontinuous matrix.
The gallic acid was accumulated at 7.64 g/L at the discontinuous matrix. The results show that the discontinuous matrix of
polyurethane is better for tannase production and gallic acid accumulation in a solid state culture bioprocess than the continuous
and semi-discontinuous matrices.
Project supported by the Agricultural, Livestock and Fishing Department (SAGARPA, No. 12385) and the National Forest Commission
(CONAFOR, No. 2004-C01-13), and the Council of Science and Technology, Mexico 相似文献
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Brian J. Baird 《期刊图书馆员》2013,64(2):275-282
Adhesives have been used for years in library binding. This article reports on the use of polyurethane (PUR) adhesive being introduced into the library binding process. This glue has been used in the publishing industry for years, and technology has now made it viable for library binding. Bridgeport National Bindery, Inc. has performed significant testing on PUR adhesive, and has demonstrated that it conforms to the ANSI/NISO/LBI Z39-78-2000 Standard for Library Binding. 相似文献
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付达新 《湖南科技学院学报》2007,28(9):71-73
聚合物防水涂料具有广泛的适用性、安全性、耐久性以及防水效果显著、性能稳定可靠、施工维修方便等优点,在建筑行业有着广阔的应用前詈。本文对永大哈弗聚氨酯彩弹防水涂料的性能进行了简要的介绍,并针对该种涂料应用中的施工方案和施工效果进行了细致的描述和分析。 相似文献
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