Does anyone have experience with low temperature prepreg?

I am using a water-soluble plug material that gets a bit soft at 75c (the lowest I can test at the moment) thought the melting temp is somewhere around 200c. As the solubility of the plug is essential to the design, I am looking into lower temp prepregs. The complexity of the part makes infusion difficult in both the multi-layer layup as well as proper resin coverage under vacuum. 

Thanks