Use aqueous solution which contains some inorganic salt or organic solvent (e.g. CaBr2, alcohol, DMF or DMAC) as gelating medium, with ploymer concentration 18%. In these methods, addition of secondary additives is the most effective.

• 用含某些无机盐或有机溶剂(如CaBr_2,乙醇,DMF或DMAC)的溶液作凝胶介质,共混物浓度为18%25,其中,以添加第二添加剂的方法最有效。