| 摘要 |
This method is used in the pharmaceutical industry. It enables the derivation of concentrated and stable water suspensions, practically without any coagulate, with small mean size of the disperse particles (between 60 and 140 nanometres), narrow allocation of the same, as well as co-polymers with larger and regulated molecular mass, whose films are elastic, strong and may be used for medical pills coating. The method entails the continual adding of co-monomeric mixture to the surface substance - nonylphenol polyglycol ether, ethoxylated with 10 moles of ethylene oxide - for 4-6 hours, heated to 75-80 degrees C, and saturated with gaseous nitrogen, also containing the substance dodecylbenzol sulphonic c acid. The addition of the initiator - ammonium per sulphate - is carried out in 5-6 equal portions for 1-1.5 hours, with the inclusion of the monomeric mixture of 2-hydroxy ethyl methacrylate or diethylene glycol methacrylate, or diethylene glycol acrylate, or their mixture. The emulsion's co-polymerisation continues for about 10 hours and is considered complete after the residual monomers become less than 0.3%. The derived suspension may be used as a film-forming material.
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