Hemofiltration Chemical Grafting Of PP And PBT Meltblown Nonwovens Modified

PP and PBT melt —blown nonwoven have been applied widely in blood filter but the filtering efficiency is low due to their poor hydrophilicity, then the modifications of nonwoven are necessary. In this paper, the main factors affecting the grafting modification of acrylic amine onto PP and PBT nonwoven initiated by different chemical initiators are studied. The experiments are as follows-.Firstly, the grafting modification copolymerization of PP melt-blown nonwoven was investigated.1.The graft copolymerization of acrylic amine (AAm) with melt—blown PP nonwoven initiated by benzoyl peroxide (BPO) was studied. The effects of conditions such as reaction time, monomer concentration, initiator concentration, preinitiation temperature and leaving agent concentration on grafting were investigated. The relation between the structure and hydrophilicity of grafting products was also discussed. The results showed that the hydrophilicity of the grafting products was improved and that the optimum reaction conditions were as follows: the leaving agent concentration of 14ml/L, the BPO concentration of 4g/L, reaction temperature of 80℃, the reaction time of 60 min, the AAm concentration of 2.5 % , the preinitiation temperature of 70℃.2.The grafting copolymerization of acrylic amine (AAm) with melt —blown PP nonwoven initiated by KMnO₄ was studied. The optimum conditions were attained by orthogonal test. The results showed that the hydrophilicity of grafting products was improved and that the optimum reaction conditions were as follows: the KMnO₄ concentration of 10×10^-3 mol/L , the H₂SO₄ concentration of 0.3mol/L , the preinitiation temperature of 50℃, the AAm concentration of 0.4mol/I., the reaction temperature of 50℃.Secondly, the grafting modification copolymerization of PBT melt-blown nonwoven was also studied.The grafting copolymerization of acrylic amine (AAm) with PBT melt —blown nonwoven initiated by KMnO₄/H₂SO₄ was studied. The effects of different conditions, such as reaction time, monomer concentration, initiator concentration, preinitiation temperature, preinitiation time and leaving agent concentration, on grafting percentage were investigated. The results showed that the hydrophilicity of grafting products is enhanced and the optimum reacting conditions as follows: the leaving agent concentration was 2%, the concentration of KMnO₄ was 1.5 × 10^-3mol.L^-1, the concentration of H₂SO₄ was 0.3mol.L^-1, the preinitiation temperature was 60℃, the preinitiation time was 60min, the concentration of AAm was 0.35mol.L^-1 the reaction temperature was 60℃, the reaction time was 3.5h.