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基于高得率浆的纤维素微纤丝的制备及其在浆张增强中的应用

2019-10-21王思魏继国张方东刘苇侯庆喜

中国造纸 2019年3期

王思 魏继国 张方东 刘苇 侯庆喜

摘要: 本研究采用化学和机械相结合的方法处理杨木P-RC APMP(木素含量22.73%),制备了一种含木素的纤维素微纤丝(Lignin contained cellulose microfibril,L-CMF),对其进行了分析和表征;并将L-CMF应用于浆张抄造,研究了L-CMF对浆张物理性能的影响。结果表明,采用TEMPO氧化法与高压均质相结合所制备的L-CMF直径约为200~400 nm,羧基含量为1165.29 mmol/kg;L-CMF能有效提高漂白硫酸盐针叶木浆(BSKP)、杨木P-RC APMP以及两者配抄后浆张的物理强度。当L-CMF添加量为7%,杨木P-RC APMP配比为30%时,L-CMF对浆张的增强效果尤为明显,浆张的抗张指数和耐破指数分别比空白样提高30.2%和50.4%;但L-CMF的加入会使浆张的松厚度、白度和不透明度略有降低。

关键词:高得率浆;P-RC APMP;含木素的纤维素微纤丝;物理强度

中图分类号:TS727+.2     文献标识码:A     DOI:10.11980/j.issn.0254-508X.2019.03.001

Abstract: To extend the application of high yield pulps, the lignin contained cellulose microfibril (L-CMF) was prepared by treating poplar P-RC APMP (lignin content of 22.73%) with chemical and mechanical methods. The resultant L-CMF was obtained by TEMPO-mediated oxidation and homogenization treatment. The L-CMF main characteristics were analyzed, and their application in enhancing handsheets physical properties was also investigated. The results showed that the diameter of the L-CMF was 200~400 nm, and carboxyl content was 1165.29 mmol/kg; the L-CMF could effectively improve the physical strength of all handsheets prepared by BSKP, poplar P-RC APMP, and the mixture of these two kind of pulps with different ratios. When the proportion of P-RC APMP in the mixtures was 30% and the dosage of L-CMF was 7.0%, the physical strength of the handsheet was improved significantly, the tensile index and burst index were increased by 30.2% and 50.4%, respectively. However, the bulk, brightness, and opacity were slightly reduced.

Key words: high yield pulps; P-RC APMP; lignin contained cellulose microfibril (L-CMF); physical properties

隨着环境问题的日益严峻,利用可再生资源取代不可再生资源(如煤炭、石油、天然气等)已成为必然趋势[1]。纤维素是地球上储量最丰富的可再生天然高分子聚合物,由于纤维素具有生物相容性、生物可降解性、价格低廉、环境友好等特点使得纤维素成为可再生资源中的最佳选择[2]

纤维素微纤丝(cellulose microfibril,CMF)最初由Turbak等人和Herrick等人提出,并于1983年分别通过机械磨解的方法制得[2-3]。通常所制备CMF的直径约为10~100 nm,长度约为0.5~50 ?m[4]。CMF的结晶度并没有纳米微晶纤维素(cellulose nanocrystal,CNC)的结晶度高,但却具有较大的长径比,相较于CNC更容易进行化学修饰,且工艺更为简单易行。由于CMF的这一特点使得CMF可以与大多数聚合物相结合制备出力学性能更好的高分子材料,因而受到了众多科研工作者的青睐[5]。……

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