【摘要】 采用电子顺磁共振(EPR)研究了漆酶/丁香酸甲酯(L/MS)对未漂硫酸盐浆纤维特性的改善。结果显示,与单独漆酶处理相比,纤维经L/MS处理后自由基浓度提高的幅度更大。L/MS处理纸浆的反应液中出现的自由基的精细结构与漆酶处理MS反应液中的自由基精细结构相同,g值与纤维上的自由基g值相同。L/MS处理纸浆的过程中,纤维中自由基的增长速度远远高于单独漆酶处理;反应后期,纤维的自由基浓度和反应液中的自由基浓度均衰减。可以推测,MS的参与使得漆酶对纤维的改性延伸至纤维内部,且MS"嫁接"在了纤维上,促进了纤维的活化。来自MS和纤维木素的酚氧自由基的交联反应致使纤维间胶合作用增强。更多还原

【Abstract】 The modification of unbleached kraft pulp with laccase in presence of methyl syringate(L/MS) was studied by electron paramagnetic resonance.The results showed that L/MS treatment caused a much higher increase of phenoxy radical concentration in fibers than laccase alone treatment.The radical in L/MS solution with pulp had the same hyperfine structure with the radical in reaction suspension for L/MS-treated pulp and the g-value was the same with that of the radicals of the fibers.The increase rate of radical concentration in fibers was much higher in L/MS treatment than that in laccase-treatment and the decay of free radicals was observed in fibers or in suspension in the later stage of the reaction.It was suggested that MS extended the enzymatic oxidation into cell wall and the MS was grafted onto the fibers,which accelerated the activation of the fibers.The cross-linking reaction of the phenoxy radicals of MS and lignin in fibers contributed to the enhancement of adhesion between the fibers.更多还原