申请人:DOW CORNING CORPORATION
公开号:EP0671434A1
公开(公告)日:1995-09-13
Process for preparing blends of VDF-based plastomers and a fluorosilicone elastomer where the blends are rich in the VDF-based plastomer, the process comprising exposing a composition comprising a VDF-based plastomer (B) to radiation, mixing a coagent (C) at a temperature of 80° to 165°C, with the composition comprising a VDF-based plastomer (B) before or after exposing (B) to radiation to provide a weight ratio of C/B from 0.05 to 0.4 where coagent (C) is a polyunsaturated compound capable of grafting to (B), forming the blend after the exposure of (B) to radiation, by mixing 5 to 46 parts by weight of fluorosilicone gum (A) with 54 to 95 weight parts of the mixture of (C) and (B) with the sum of (A) + (B) + (C) being 100 weight parts and (A)/(B) equal to 0.05 to 0.9, heating the mixture of (A), (B), (C) at a temperature of 80° to 140°C, adding a free radical initiator (I²) to the blend where the free radical initiator is characterized by a half life time of about 1 hour at a temperature equal or higher than 135°C and heating to crosslink the blend.
制备VDF基弹性体和氟硅弹性体混合物的工艺,其中混合物富含VDF基弹性体,该工艺包括将包含VDF基弹性体(B)的组合物暴露于辐射,在将(B)暴露于辐射之前或之后,在80°至165°C的温度下将助剂(C)与包含VDF基弹性体(B)的组合物混合,以提供重量比为0.05至0.4 其中助剂(C)是能够接枝到(B)上的多不饱和化合物,在(B)暴露于辐射之后形成混合物,方法是将 5 至 46 重量份的氟硅胶(A)与 54 至 95 重量份的(C)和(B)混合物混合,(A)+(B)+(C)的总和为 100 重量份,(A)/(B)等于 0.05至0.9,在80°至140°C的温度下加热(A)、(B)、(C)的混合物,向混合物中加入自由基引发剂(I²),其中自由基引发剂的特点是在等于或高于135°C的温度下半衰期约为1小时,然后加热使混合物交联。