of thermoplastic fluoropolymers that may be used with this invention are copolymers having the following combination of monomers ctfe vdf ctfe tfe ctfe tfe hfp ctfe tfe hfp vdf ctfe tfe hfp vdf ppve ctfe tfe e tfe hfp tfe vdf hfp tfe p tfe pve bromine or chlorine containing e tfe copolymers and bromine or chlorine containing tfe hfp vdf copolymers as mentioned above the fluoropolymer has improved bonding properties to other substrates particularly in the presence of an organic compound having hydride functions mh additionally by including this compound in the fluoropolymer composition a peroxide curable fluoropolymer composition can be obtained examples of the organic compound include siloxanes or silazenes that comprise one or more mh functions typically when the organic compound is a siloxane or a silazene the mh functions will be u2014 sih functions preferably the sih function will be an u2014 osih or a u2014 nsih whereby the hydrogen is attached to a silicon atom that is further bonded to an oxygen or nitrogen atom the siloxane of silazene may be a simple low molecular weight organic compound or may be a polymeric compound including for example a polysiloxane which may be linear branched or cyclic specific examples include hsi och 2 ch 3 3 ch 3 2 ch 3 ch 2 o sih 1 1 3 3 tetraisopropyl disiloxane diphenyl 1 1 3 3 tetrakis dimethylsiloxy disiloxane available from united chem silylhydride terminated poly.