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利用交叉极化结合魔角旋转技术13C核磁共振法(CP/MAS 13C NMR)对桉木浆纤维的微观结构进行研究,为进一步研究木质纤维素材料开发过程中反应障碍特征奠定基础.通过对NMR光谱C1区(δ102～108)进行洛仑兹拟合,得到桉木浆纤维中纤维素Iα的相对含量为26.92%,纤维素Iβ的相对含量为52.04%,主要以纤维素Iβ晶体形式为主.通过计算纤维素C4结晶区(δ86～92)和非结晶区(δ80～86)的相对含量得到桉木浆的纤维素结晶度为47%.通过洛仑兹和高斯函数的混合模型对NMR光谱C4区(δ80～92)进行拟合得到基原纤尺寸和微原纤横向尺寸分别为4.0与17.9nm,并通过计算不同形态的结晶纤维素的相对含量得到纤维素结晶度为51%,证实了在微原纤内部次晶纤维素的存在.
The microstructure of eucalyptus pulp fibers was studied by means of cross polarization combined with magic horn rotation technique (13C NMR), which laid the foundation for the further study on the characteristics of reaction disorder during the development of lignocellulosic materials. The Lorentz spectra were obtained in the C1 region (δ102 ~ 108). The relative content of cellulose Iα in Eucalyptus pulp fibers was 26.92%, and the relative content of cellulose Iβ was 52.04%, mainly in the form of cellulose Iβ crystal The cellulose crystallinity of eucalyptus pulp was found to be 47% by calculating the relative contents of the crystalline regions (δ86-92) and non-crystalline regions (δ80-86) of cellulose C4.The NMR spectra of the eucalyptus pulp were analyzed by a mixed model of Lorentz and Gaussian functions Spectral C4 region (δ80 ~ 92) were fitted to obtain the basis of fibril size and microfibril lateral size of 4.0 and 17.9nm, and by calculating the relative content of different forms of crystalline cellulose obtained cellulose crystallinity was 51% The presence of subcrystalline cellulose inside the microfibrils was confirmed.