4 results about "Vinylacetic acid" patented technology

The invention relates to water-soluble polysiloxane as well as a preparation method and application thereof. The preparation method of the water-soluble polysiloxane comprises the following steps: mixing lipase, trehalose and a surfactant to prepare modified lipase; vinyl acetate, alkoxy silane, monomethoxy polyethylene glycol and the modified lipase are mixed, and the water-soluble polysiloxane is prepared. According to the preparation method, the lipase is coated with the trehalose to form the modified lipase, so that the modified lipase can keep efficient catalytic activity for a long time at a relatively high temperature, and further the water-soluble polysiloxane can be efficiently prepared through a lipase catalytic reaction one-step method. Compared with a traditional acid / alkali synthesis method, the preparation method of the water-soluble polysiloxane can obtain a higher conversion rate at a lower reaction temperature, meanwhile, an antioxidant does not need to be added, and the obtained water-soluble polysiloxane is good in water solubility, light transmittance and safety.

This application relates to water-soluble polysiloxanes, their preparation methods, and applications. The preparation method of water-soluble polysiloxanes includes: mixing lipase, trehalose, and a surfactant to prepare a modified lipase; and mixing vinyl acetate, alkoxysilane, monomethoxy polyethylene glycol, and the modified lipase to prepare the water-soluble polysiloxane. This preparation method utilizes trehalose to coat the lipase, forming a modified lipase that maintains high catalytic activity at higher temperatures for extended periods. This allows for the efficient one-step preparation of water-soluble polysiloxanes via lipase-catalyzed reactions. Compared to traditional acid / base synthesis methods, this method achieves higher conversion rates at lower reaction temperatures, eliminates the need for antioxidants, and yields water-soluble polysiloxanes with good water solubility, light transmittance, and safety.

This invention belongs to the field of biochemical technology, specifically disclosing a 6′- O A whole-cell biosynthesis method for caffeoyl arbutin and its analogues includes the following steps: using aromatic carboxylic acids and vinyl acetates as substrates, performing a transvinylation reaction under palladium catalyst and base conditions to prepare aromatic vinyl esters; using the prepared aromatic vinyl esters as acyl donors, ... β Arbutin, using acyl acceptors, undergoes an aromatic acylation reaction in an organic solvent with whole cells of Aspergillus oryzae as a catalyst to yield the 6′- O Caffeoyl arbutin or its analogues. This invention develops a two-step whole-cell catalytic method for the efficient and sustainable synthesis of CA and its analogues. The synthesized compounds exhibit potent inhibitory activity against mushroom tyrosinase. This invention pioneers a novel green biosynthetic pathway for tyrosinase inhibitors, demonstrating significant application potential in the food preservation and cosmetics industries.

The invention belongs to the field of rare earth separation, and particularly discloses a separation method of heavy rare earth ions. According to the separation method, a vinyl complexing agent comprising at least one of vinylphosphonic acid, vinylsulfonic acid, vinylacetic acid or 4-vinylbenzyl chloride is adopted to selectively complex heavy rare earth ions in a water phase, so that the partition coefficient among different heavy rare earth ions is obviously improved; and extracting and separating different heavy rare earth ions from the water phase of the complex containing the heavy rare earth ions and the organic phase containing the extracting agent to achieve the purpose of improving the separation efficiency.