Study Of Performance On The New Device For Preparing Micro-nano Alternating Multilayered Conductive Composites

Along with the social development the demand for plastic products hasbecome higher. In the past, the development of plastics industry mainlydepended on the research and application of insulator. The techonologies ofpreparing conductive plasitc developed fast as a result of the increasingdemand and exploration of conductor, semiconductor even superconductor.The microlayer coextrusion technology was firstly presented by Americanscientists in the late1960s, which could combine two or more types ofpolymers into composites with hundreds or thousands of alternate layerswhose thickness even reached nanometers. For decades' development, it hasbeen transiting from stage of scientific research to industrial application. Thispaper focused on the conductivity of composites with alternating multilayerstructure based on the microlayer coextrusion technology.Firstly, this paper summarized preparation methods of conductive plastic,and concluded different conductive theories. The development and currentsituation were also summed up, and the forming principles of microlayer coextrusion was emphacially described. A novel microlayer coextrusiontechnology was proposed with more advantages.Secondly, multiplying element was emphatically introduced as the coreunit, including the design of structure and molding principle. The experimentalresults showed that novel multiplying element had better layered effects andefficiency compared with tranditional lapped ones. It increased number oflayers with2ⁿ⁺¹, and the thickness of microlayer was uniform in accordancewith speed of extruding screw and thickeness of die.Thirdly, the conductivity of composites with different conductive fillerswas primarily studied using own microlayer coextrusion devices comparedwith that of composites in traditional processing method. The results showedthat alternating multilayer composites could reduce the percolation thresholdsignificantly through double percolation phenomenon and then reduce cost. Asa result of increasing number of layers, the morphology of fillers dispersing inpolymer matix changed, then adversely affected conductivity of composites.The mirolayer structure embodied various effects on dispersing morphologiesof CB and SSF in PP matix. Former mainly reflected in the destruction of CBaggregate and chain structure, latter reflected in the orientation of SSF, leadingto anisotropy of conductivity.Lastly, the channel of multilying element consisted of four channelswhose flowing distance were different, so flowing uniformity was destroyed.Using ANSYS software optimize structure of channels of multilying element., and results showed that just changing the demensions of upper and netherchannels could meet the demands. Furthermore, Suggesting adopting T-styledie instead of that with damping block, which could destroy the mirolayerstructure, ideal demensions also were achieved by simulating and analysing.