Surface Treatment Of UHMWPE Fiber And Its Performance In Cement Mortar

Ultra-high molecular weight polyethylene（UHMWPE）fiber has a prospect usedextensively in the fields of national defense，construction，medical treatment，aviation andnavigation， etc.because of very low density， high-strength， high-modulus， excellentimpact resisitance and corrosion-resistance and so on.However，the fiber is of chemicalinertion，low surface energy，lack of polar groups，and highly symmetric methylenestructure，the fiber has a high degree of erystallinity and orientation..It is therefore ofneeessity to solve this problem.There are many methods for the treatment of UHMWPEfibers，but these methods have many shortcomings even at defects.In addition，there has notyet been studied in depth performance characteristics for it’s application in cement mortar.UHMWPE fibers were treated by chromic acid， KH570， PVA， HPMC， andSCA-PAA-C.Scanning electro micrograph（SEM）.Contact angle were employed to show thechanges of the surface properties of the fiber.And single fiber strength experiment was used toshow the strength loss because of the treatments.Using the flexural strength，compressivestrength and bending toughness test trial investigated the fiber reinforced mechanicalproperties of mortar.Washing method was used to investigate the relationship between thefiber surface treatment and dispersion effect，while establishing a relationship of decentralizederror and strength of reinforced cement material.Untreated UHMWPE fibers with twomodified methods were made into cement mortar.The results showed that the treated fiber had a better effect to reinforce cement mortar.Inaddition，the modified effect of low denier fibers was superior to high denier with chromatetreatment solution.In addition to the active treatment agent KH570，PVA，HPMC having afunction of improving wettability of the outer surface of the fiber，UHMWPE fiber surfaceafter SCA-PAA-C treated is more rough than untreated，and the concrete matrix bindingsurface increased. In terms of the stability of the mix to improve the degree of fiberdispersion，KH570treated fiber was the maximum.In the large gap between the relativedispersion error，fiber dispersion degree of influence in the mortar on the strength of thetreated fibers was signifycantly greater than the degree of influence on the strength of the mortar. It was found that UHMWPE fiber has a good effect to improve the performances ofcement mortar.The results indicate that the treated fiber in cement matrix could improveimpact performance of the mortar.