Researches On Pivotal Technology Of Alginate Functional Modification

In this study,the enhanced calcium alginate fiber with double network structure and thermo-regulated calcium alginate/polyethylene glycol acrylate fiber with double network structure are prepared by chemical methods and conventional wet spinning.The reinforcement of calcium alginate is accomplished by introducing of polyacrylamide crosslinking network and double network structure.The immobilization of polyethylene glycol acrylate is accomplished by introducing covalently crosslinking polyethylene glycol acrylate and double network structure.The fibers obtain thermo-regulating property,simultaneously.Fourier transform infrared spectroscopy,Electronic yarn strength tester,Electronic single fiber strength tester,Differential scanning calorimetry,Dynamic mechanical analysis,Thermal gravimetric analysis,X-ray diffraction analysis,Scanning electron microscopy,Polarizing optical microscopy,et al.are used for characterizing the chemical structure,physical and mechanical property,thermo-regulated property,thermal stability and morphology,et al.The results show that reinforcement of calcium alginate fiber is significant.The increasing range of breaking strength is up to 75%.The fiber is stable under 400 ?.Thermal degradation capacity increases along with content increasing of covalent crosslinking network.Double network has negative effects on crystallization.Dynamic mechanical analysis shows that breaking strength is affected by concentration of covalent network,entanglement of two networks and their interactions,collectively.Breaking strength is non-linear related with crosslinking density.Calcium alginate/polyethylene glycol acrylate thermo-regulated double network fiber has crystallization peak at 37.5 ?,which is close to the temperature of human body.And the crystallization enthalpy is 68.73J/g.The loss rate of crystallization enthalpy is 11%in the processing.It reflects good results of immobilization.The fiber is stable under 200 ?.The enthalpy gets lower with the increasing crosslinking density of polyethylene glycol acrylate covalent network.But the thermal stability increases at the same time.Calcium alginate/polyethylene glycol acrylate thermo-regulated double network fiber remains good mechanical strength during modification.The loss of strength is 4.59%.Calcium alginate fiber with great mechanical property and themo-regulated property is obtained by conventional wet spinning process,in this work.The processing is simple,easily cperable and non-polluting.The cost and eneery consumption are lower.The pivotal technology of reinforcing modification and thermo-regulating modification by double network has great prospects for industrial and commercial applications.