Preparedinsitupolyisoprene/Carbonnanotube Nanocomposites

Exploring polyisoprene/multi-walled carbon nanotubes nanocomposite in-situ polymerization method,we aims to create an nano-specific Ziegler-Natta catalyst that can solve the problem of dispersion and interfacial adhesion of MWCNTs and polyisoprenenanocomposite.Providean effective method for preparing Polyisoprene/MWCNTs nanocomposites and eliminate obstacles to large-scale application in situ polymerization technique key technical problems.(1) prepared the titanium-basedand Ziegler-Natta catalyst using high energy ball milling. Then with the use of co-catalyst in situ bulk polymerization to design polyisoprene/multi-walled carbon nanotube composites. The keyscientific issue for influence the dispersion of MWCNTs is the strong π-πinteraction, leading to the aggregation of MWCNTs in nanocomposite. In order to solve thisproblem, We use MWCNTs (including multi-wall carbon nanotubes and multi-walled carbon nanotubes hydroxylation two kinds)/MgCl2 (magnesium chloride) as the carrier, load titanium Ziegler-Natta catalysts in situ with high-energy ball milling, prepared a novel MWCNTs/MgCl2/titanium tetrachloride catalyst. This catalytic system can break the original study only use of expensive metallocene catalyst by chemical grafting method limited to the carbon nanotubes. Under the action of triisobutylaluminum cocatalyst achieve isoprene monomer with MWCNTs/MgCl2/titanium tetrachloride catalyst, can be used to achieve in situ polymerization on the surface and polyisoprene molecular chain growth efficiently. Good dispersion effect by coating polyisoprene molecular chain of carbon nanotubes to weaken the strong intermolecular force between the carbon nanotubes forming the carbon nanotube so as to avoid a strong aggregate structure in order to achieve a carbon nanotube. MWNTs connection polyisoprene can be well dispersed in the rubber matrix polyisoprene.(2) Enhance the polyisoprene matrix interfacial interaction with carbon nanotubes: The key issue to enhanced MWCNTs matrix is improving the interaction betweenMWCNTs and nanocomposite. Althoughwe can obtained MWCNTs well dispersion by in situ polymerization, MWCNTs is difficult to reinforce mechanical properties of PIP matrix due to the weak interaction This revealed that he effective entanglement of PIP chain is probably related tothe matrix molecular weight. We prepared polyisoprene matrix with a high molecular weight, that can achieve the polyisoprene effective entanglement of carbon nanotubes, thus no chemical bonding or any other special mutual under the influence cases that rely solely on physical action to achieve polyisoprene molecular chain entanglement of carbon nanotubes effectively, then improving MWCNTs/polyisoprene mechanical properties of the composites.(3) In this article,we use the efficient ball milling system prepare the catalyst,in the triisobutylaluminum cocatalyst explore the effects of nTi/nIp and nAl/nTi, prepolymer on the isoprene polymerization initiator catalytic efficiency, the process structure of the product, etc.; By 13C-NMR、1H NMR, FTIR to characterize the microstructure of polymeric products. To characterize the dispersion state of the carbon nanotubes by scanning electron microscopy in the preparation of the catalyst and polyisoprene matrix.(4) The composite material properties:thermal stability of composite materials: carbon nanotubes can be added to improve the thermal stability of the composite material and the thermal stability of the type of carbon nanotube composites smaller; mechanical properties:PIP/carbon nanotube composites storage modulus, elongation at break and tensile strength is improved.