| High strength and high modulus polyethylene(UHMWPE)fiber,as one of the three high performance fibers,has been applied in many fields.It is of high strength and high modulus,in other industries have emerged as a high performance fiber,its density is less dense than water,this is the one and only in high performance fibers.In this paper,the dispersion of UHMWPE fiber,the preparation of the paper,and the related properties were studied.In this paper,UHMWPE short cut fiber was used as raw material to prepare paper.Study on the preparation technology of UHMWPE fiber paper is mainly divided into two parts,respectively is the dispersion of UHMWPE fiber and the wet forming process for paper.First of all,in the study of the dispersion process of the fiber,the types and the amount of chemical additives used in fiber dispersion were discussed.The chemical structure of UHMWPE fiber have no active groups,it is not hydrophilic,and the density is less than 1,showing the floating state in water.With osmosis agent,the interfacial tension of fiber in water reduced,then add auxiliary dispersant PEO,can make the fiber dispersed.The pretreatment method of the pretreatment agent was compared,and the most effective pretreatment method was selected.In the wet forming process,adding the carboxylated styrene butadiene rubber latex,cationic polyacrylamide,PEO,carboxyl styrene butadiene latex provides carboxyl group,and it can form a chemical bond with cationic polyacrylamide,which can play an important role in strengthening and retention of fiber.With the detection of intensity,SEM image,paper formation properties,to explore the optimal dosage of chemical additives,the final optimization of penetrant SF dosage is 9%,dosage of carboxylated styrene butadiene rubber latex is 8%,cationic polyacrylamide dosage is 0.9%,dosage of PEO is 0.1%.UHMWPE paper s strength is very poor,the main strength is given by the following process,including resin impregnation and hot pressing,in subse?uent experiments,this paper discusses the hot pressing process,pressing the paper as a whole force structure,rich strength of paper.Mainly discusses the effect of hot pressing temperature and pressure on the properties of paper.As the hot pressing temperature is increased from 130? to 150?,the tensile index changes from 8.44 N·m·g-1 to 71.8 N·m·g-1.At 155?,the paper appears shrinkage deformationand,and finally determine the optimum hot pressing pressure is 15 MPa,the hot pressing temperature is 150?.The properties of UHMWPE fiber paper prepared by the best wet process were examined,including thermal stability,acid and alkali resistance,pore size,basic weight,thickness,strength,etc..The results showed that the melting point of UHMWPE fiber paper was higher than that of the original fiber,the thermal decomposition temperature was higher than that of the original fiber,and the paper,s thermal stability was better.UHMWPE fiber paper was treated with acid and alkali,and it was proved that the new chemical bond appeared in UHMWPE fiber paper after H2SO4 treatment,however,NaOH treatment did not cause new chemical groups on the paper,mainly because of the corrosion of non crystalline area.After acid and alkali treatment the tensile index of UHMWPE fiber paper are decreased,overall,after acid treatment after 48 h,tensile strength retention rate can be maintained above 80%,and the strength is still very good.The feasibility of preparing conductive paper by UHMWPE fiber is good.UHMWPE fiber conductive paper was prepared by coating method,With the increase of the coating amount of CNT and GNS,the resistivity of UHMWPE fiber conductive paper is rising.The resistivity of CNT increased by about 13 orders of magnitude to about 10-3·m-1,while the resistivity of GNS increased by about 5 orders of magnitude up to 10-11S·m-1,the percolation thresholds are obtained at about 0.4% and 0.3%,respectively.The percolation threshold and conductivity decrease with the increase of the basic weight. |
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