Study On Dope Dyeing With Melt Spinning Of Ultra-high Molecular Weight Polyethylene Fiber

This paper studied the method that adding the modified agent of low density polyethylene to the ultra-high molecule weight polyethylene?UHMWPE?to improve the bound node in large molecules of UHMWPE and to increase the melt liquid,and then acquired the melting fiber of UHMWPE,and at last adopting the dope dyeing to produce the melt-spinning UHMWPE fiber.Firstly,it was studied by the test of pigment particle size,heat resistance and hydrophilic in this paper as the dope dying requested.Selected three kinds of pigment that included iron oxide red Fe₂O₃ iron oxide yellow ZnFe₂O₄ and phthalocyanine blue,and then modified the inorganic pigment iron oxide red and iron oxide yellow which has lower hydrophilic.Studied on the effect of modified pigment by the oil-absorbed value,zeta potential,FTIR,SEM,contact angle and etc.And then add the pigment to the two system which was ultra-high molecule weight polyethylene and polyolefin increasing the liquidity of blend system which quality ratio was 5:5and 6:4.Fixed the adding amount of pigment by the real-time torque mixer output.Then through twin-screw extruder to granulate,studied the spinnability of all blending masterbatch by RH7 double tube capillary rheometer,then produced the colored fiber by min-lab double-screw spinning mechanism and drafting colored fiber.The crystallinity and mechanical properties of fiber were tested.Studied the proprieties ofdope dyeing fiber onK/S value,color fastness and the strength.The study show that the iron oxide red Fe₂O₃ modified by silane coupling agent,iron oxide yellow ZnFe₂O₄ modified by titanate coupling agent and phthalocyanine blue was improved that the effective surface bonding modifier,has good hydrophobicity,the contact angle above to 150 degrees,Zeta potential beyond 40mV,the inorganic pigment from hydrophilic to hydrophobic and the compatibility of modified pigments in UHMWPE blend system was significant improved.At the same temperature,the pigment provided lubrication in blend system reduced the system viscosity when the mass ratio of pigment in the blend system is less than 1%,with the rising of the pigment content,the rheological property enhanced and the property of spinning performance,spinning and drafting was deceased.When adding 3%unmodified inorganic pigment,the colored fiber was broken heavily,through adding5%the inorganic pigment modified by coupling agent,the fiber still has good spinnability.The mechanics performance of colored fiber which adding unmodified pigment was declined significant compared with modified pigment in same amount.In the optimal process,with the mass ratio between ultra-high molecular weight polyethylene and polyolefine 5:5,the broken strength of red fiber that pigment was modified by titanate coupling agent was reached 615.51MPa,K/S value of 13.277,the wet rubbing fastness level 4,dry rubbing fastness level 5,sunlight fastness 7-8.The broken strength of blue fiber which adding phthalocyanine blue pigment was668.03MPa,K/S value of 14.004,the wet rubbing fastness level 4,dry rubbing fastness level 5,sunlight fastness 7-8,but when the mass ratio between ultra-high molecular weight polyethylene and polyolefine is 6:4.