Study On Interfacial Interaction And Dispersion Mechanism Between Rubber And MWNTs

Carbon nano tube (CNT) has been considered as an excellent candidate for preparing polymer composites due to its excellent mechanical and functional performances.There are lots of researchers focusing on the interface between rubber and MWNTs, because it is considered as ideal reinfocing fillers, but there is no unified conclusion in the role of carbon nanotube and rubber interface. In order to study the interfacial interaction between MWNTs and natural rubber, and how different types of MWNTs influence the interfacial interaction between carbon nanotubes and natural rubber, so four main aspects of research work have been studied:1. A research of the interaction between multiwall carbon nanotubes (MWNTs) and natural rubber (NR) was studied. The results showed that NR/MWNTs(100/5) compound’s BR is 22.04, which is identical to NR/CB (100/50) compound’s, and bound rubber was consisted of two parts, one is loose bound rubber, other is tight bound rubber. The result of LF-NMR indicated that the mobility of rubber chains in the tightly bound rubber is reduced compared with loosely bound rubber, which is more restricted than NR. And the thickness of rubber layer adhered on MWNTs surface in the bound and tight bound rubber is ～13 and ～8 nm by SEM. FTIR and Raman spectra of the composites show evidence for the presence of CH group interactions with MWNTs.2. F9000 were characterized by HR-TEM, Raman and XPS. The result of HR-TEM and Raman indicated that MWNTs exist lots of defects. The result of XPS indicated 4% O element was found in the MWNTs, mainly functional group is hydroxy. So there were three interaction mechanisms between MWNTs and NR:Firstly is topological constraints exerted on chain segments by the appropriate (geometrical) elements on the surface of the filler particles, secondly is covalent interaction, lastly is noncovalent interaction, such as wrapping.3. We selected carbon nanotubes with different structural characteristics and studied it’s influence to NR/MWNTs composites by mechanical mixing preparation methods. The results showed that the BR increased with the increasing of ID/IG of MWNTs, which means the more defects in the MWNTs, the better interaction in MWNTs and NR, furthermore, the modulus NR/MWNTs composite increased with the increasing of ID/IG.4. We selected three kinds of MWNTs(F7000, F9000 and GM3) as experimental materials to research the mechanical properties, thermal conductivity, electrical conductivity in composites. It’s obvious that with the more dosage of MWNTs, the better performance on mechanical properties, thermal conductivity, electrical conductivity. When it comes to the same dosage of different kinds of MWNTs, their performance decreased as the sequence of F7000, which exist more defects, F9000 and GM3, which exist less defects.