摘要:
A process for making glycerol di-tert-butyl ethers is disclosed. In one aspect of the invention, glycerol and isobutylene react in the presence of a β-zeolite having a silicon to aluminum ratio greater than 150. In another aspect, the etherification is performed in the presence of a β-zeolite and added tert-butyl alcohol. Each process selectively provides glycerol di-tert-butyl ethers while reducing the generation of isobutylene dimers and trimers. Utilizing both aspects of the inventive process simultaneously affords a diether product mixture containing less than 5 wt. % of isobutylene oligomers.
摘要:
A two-step, base-catalyzed process for making crosslinked polyvinylpyrrolidone (PVP-P) having a low swell volume is disclosed. A crosslinker is generated “in situ” in the first step by heating a basic aqueous mixture containing a relatively low concentration of N-vinylpyrrolidone under added inert gas pressure. In a second step, the reactor temperature is reduced to initiate polymerization. The process is a productive way to make PVP-P that is easy to isolate and purify. The polymer has a swell volume less than about 40 mL H2O/10 g polymer, which makes it valuable for beverage clarification.
摘要翻译:公开了一种用于制备具有低膨胀体积的交联聚乙烯吡咯烷酮(PVP-P)的两步碱催化方法。 通过在加入的惰性气体压力下加热含有较低浓度的N-乙烯基吡咯烷酮的碱性含水混合物,在第一步骤“原地”产生交联剂。 在第二步中,降低反应器温度以引发聚合。 该过程是使PVP-P易于分离和纯化的有效方式。 该聚合物具有小于约40mL H 2 O / 10g聚合物的溶胀体积,这使得它对于饮料澄清是有价值的。
摘要:
A process for making crosslinked polyvinylpyrrolidone (PVP-P) is disclosed. Crosslinker generation, followed by polymerization of NVP, gives a polymer containing up to 4 wt. % of residual NVP. An aqueous mixture of the polymer is then heated in the presence of a protic acid at pH
摘要翻译:公开了制备交联聚乙烯吡咯烷酮(PVP-P)的方法。 交联剂生成,随后是NVP的聚合,得到含有至多4wt。 剩余NVP的百分比。 然后在pH <4的质子酸存在下加热聚合物的水性混合物以消除NVP。 最后,用碱金属氢氧化物水溶液中和PVP-P。 该方法产生低毒性废水(<20 L / kg PVP-P)的体积减少,并产生符合重要产品规格的PVP-P。