摘要纤维素是世界上来源丰富，取材方便且含碳量高的绿色资源，在日常生活中随处可见，但由于本身含大量羟基，使得纯纤维素的制品柔顺性差且刚性较强，然而通过接枝改性的方法可以很好的解决纤维素柔顺性差等问题。桑枝纤维（MBC）和竹纤维（BBC）都是来源广泛的可再生物质，其中桑枝纤维素含量为38%左右，本文利用离子液体为溶剂，将桑枝纤维与竹纤维进行接枝来制备复合纤维（MBCC），该复合纤维兼具桑枝纤维与竹纤维的特性，很好的克服了柔顺性差、刚性过强等缺点，所以该复合纤维可以应用于食品保鲜膜、医用敷料、透析膜等材料的制备中。

本实验首先合成三种离子液体（[DMIM][DMP]、[EMIM][DEP]、[BMIM][Cl]），并对三种离子液体进行了功能筛选，结果表明离子液体[EMIM][DEP]在90 ℃，1 h的条件下溶解微晶纤维素（MCC）的效果最好，纤维素溶解率为100%；配制了六种浓度分别为0%，4%，8%，12%，16%和20%的NaOH溶液，将桑枝粉与竹枝粉进行润胀等处理，结果表明当使用浓度为16%及以上的NaOH溶液润胀桑枝纤维与竹纤维时，桑枝粉与竹枝粉的失重率达到60%，在离子液体中90℃溶解1h，溶解率高达100%；以离子液体为溶剂，对桑枝纤维与竹纤维进行接枝改性，制备了桑竹复合纤维，并进行傅里叶红外表征，结果表明桑竹复合纤维成功将长纤维与短纤维融为一体，进而制备了桑竹复合纤维膜，并放置于pH分别为5。3，6。8和8。0的PBS缓冲液中进行了吸水率、溶胀率和孔隙率等性能测试，其中桑竹复合纤维的溶胀率为96。4%，孔隙率为60。49%，结果表明其在酸碱条件下具备了良好的溶胀能力，是一种性能优良的复合纤维。84320

毕业论文关键词：接枝改性；碱处理；离子液体；桑枝纤维；竹纤维

Abstract Cellulose is a kind of rich resource which we can easy to take and itself contains high carbon content over the world。 It could be seen everywhere。 But it has a lot of hydroxyl groups which makes the pure cellulose products less flexible and stronger rigidity。 and by using grafting change method to solve the poor compliance of cellulose。 Mulberry cellulose(MBC) and bamboo cellulose(BBC) are the renewable resource which they could be found easily。 Mulberry cellulose contain is about 38%。 In this experiment, by using ionic liquid as solvent and grafting bamboo cellulose with mulberry cellulose to product mulberry bamboo composite cellulose(MBCC)。 The composite cellulose has the both characteristics of mulberry cellulose and bamboo cellulose, it also overcomes the disadvantages of the cellulose's poor flexibility and strong rigidity。 So the composite cellulose could be used in the preparation of food, medical dressing, dialysis membrane and other materials just because its excellent properties。

This experiment synthesized three types of ionic liquids ([DMIM][DMP], [EMIM][DEP], [BMIM][Cl]) firstly。 And the ionic liquids were functional screening by using microcrystalling cellulose (MCC)。 The result showed that when we dissolved MCC one hour at 90, ionic liquids [EMIM][DEP] could dissolve MCC at 100 percent。 Secondly, we prepared six concentrations NaOH solution, they were 0%, 4%, 8%,  12%, 16% and 20%。 And then we put mulberry powder and bamboo powder into them。 The results showed that when we used 16% concentration NaOH solution or above, the weight loss rate of mulberry cellulose and bamboo cellulose were 60% 。 And they could dissolve in the ionic liquid at 100 %。 We grafted the bamboo cellulose with mulberry cellulose with ionic liquid, and we got the mulberry bamboo composite cellulose。 Then we carried on the Fourier transform infrared spectroscopy。 It showed that MBCC blended the long cellulose with the short cellulose successfully。 After that, we prepared MBCC film and placed into PBS buffer solution which their pH were 5。3, 6。8 and 8。0 to test their performance, including water absorption rate, swelling rate and porosity。 The results showed that the swelling rate of MBCC film was 96。4%, the porosity was 60。49%。 It showed that MBCC film was a type of excellent performance composite film and it could maintain good swelling capacity in acidic or alkaline conditions。