Study On The Modification And Nanoscale Interpenetrating Network Morphology Of Fluoroelastomer

Interpenetrating polymer networks (IPNs) are relatively special types of polymer blends where one or both phases are cross-linked. Depending on the blend ratio, morphology, cross-link density and nature of component polymers, the IPNs show characteristic properties. IPN preparation is considered as the unique way of restricting phase separation in immiscible polymer blend. Due to the unique arrangement of the two phases in an IPN, these materials often exhibit good mechanical strength and toughness. IPNs technology has widely applied in modification of polymer materials. Fluoroelastomer (FKM) is used as a specialty polymer in a variety of applications such as seals, O-rings, tubes, hose and cables. It is well known for their resistance to heat and aggressive fluid environments. However, the poor flexility at low temperature limits some of its application. In this thesis, in terms of some unique idea, a series of new FKM IPNs with improvement properties, have been successfully prepared by using four technique approaches, the relation between structure, morphology, composition and properties were investigated systematically. The main results obtained are summarized as follows:1. The preparations of interpenetrating polymer networks (IPNs) based on fluoroelastomer/ butadiene-acrylonitrile rubber (FKM/NBR) by molten blending at high temperature, shear process and respective chemical cross-linked of two components was investigated.2. The morphology and thermodynamics for FKM/NBR IPNs were investigated by transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMA). Special focus was placed on the phase continuity since it strongly influences the mechanical properties of the polymer blend. The influence of the two networks component on the mechanical properties and thermostabilities was studied. Base on the results of the morphology and mechanical studies, the excellent mechanical properties of the FKM/NBR IPNs were caused by the synergistic effects of co-continuous phase with small phase domains of 50-200nm and perfect interpenetrating network structure. Mechanical testing indicated a synergistic effect at the 80/20 FKM/NBR with maximum values for both...