248nm深紫外光刻胶

本文从化学增幅技术的产生，深紫外248nm胶主体树脂及PAG发展历程、溶解抑制剂、存在的工艺问题及解决途径多个方面综述了深紫外248nm胶的发展与进步．     

Industrial application of Nafion-systems in rearrangement-aromatisation, transesterification, alkylation, and ring-closure reactions

Nafion, a perfluorinated sulphonic acid ion-exchange polymer, is known to be a very strong Brønsted acid. Thus, Nafion NR 50 and Nafion/SiO₂ with 15 wt.% Nafion-loading were selected, in order to elucidate the potential for rearrangement-aromatisation of ketoisophorone (KIP) to 2,3,5-trimethylhydroquinone diacetate (TMHQ-DA) in presence of acetic acid anhydride as acylating agent, transesterification of TMHQ-DA to 2,3,6-trimethylhydroquinone monoacetate (TMHQ-1-MA) and reaction of isophytol (IP) with trimethylhydroquinone (TMHQ) to (all-rac)--tocopherol. For the rearrangement-aromatisation of KIP to TMHQ-DA supported Nafion/SiO₂ was markedly more active than the unsupported Nafion NR 50. Both Nafion-systems generally revealed remarkably high selectivity, which ranged up to 94 GC-a% TMHQ-DA at high conversion. The major side-product was 3,4,5-trimethylcatechol diacetate. In case of Nafion/SiO₂, pre-treatment under vacuum and especially grinding of the extrudates seemed to increase activity at comparably high selectivity. Recycling Nafion/SiO₂ after filtering and rinsing with acetic acid anhydride led to gradually decreasing activity. Without intermediate isolation of TMHQ-DA, Nafion/SiO₂ was active and selective for the formation of TMHQ-1-MA. Using the Nafion systems in the reaction of IP and TMHQ revealed that remarkably high conversion of IP (>95%) and compared with zinc chloride/Brønsted acid or BF₃-catalysed reaction good yields (≈92%) and selectivities were obtained. We found a strong dependency on the solvent polarity. In further experiments, the recovery of the catalyst was tested.     

微波辐射酸催化喜树种子油制备生物柴油工艺

研究了在微波辐射条件下硫酸催化酯交换反应转化喜树种子油制备生物柴油的工艺,同时采用HPLC分析了生物柴油产品中主要脂肪酸甲酯成分及其质量分数。通过实验考察了醇油摩尔比、反应时间、反应温度、催化剂加入质量分数对反应的影响,并得出了在微波辐射下硫酸催化喜树种子油制备生物柴油的最佳工艺条件:醇油摩尔比15∶1、微波辐射时间40 min、反应温度70℃、催化剂加入质量分数(与原料油)3%,转化率可达95%以上。结果表明,与传统硫酸催化酯交换反应相比,该方法具有催化剂加入质量分数少、反应温度低、时间短和转化率高等优点,对工业化制备生物柴油提供了科学参考价值。