摘要
基于一维漫反射近红外(NIR)光谱及一维原位漫反射NIR光谱分别研究了乙基纤维素分子结构及平均吸收频率/吸收强度。基于二维原位漫反射NIR光谱进一步研究了乙基纤维素分子官能团变化快慢顺序。实验发现,乙基纤维素分子结构的NIR光谱吸收模式主要包括:CH3官能团中红外(MIR)不对称弯曲振动模式(δ_(asCH3-一维-MIR))的2级倍频(ν_(1-一维-NIR))、缔合O-H官能团MIR伸缩振动模式(ν_(O-H(缔合)-一维-MIR))的1级倍频(ν_(2-一维-NIR))、缔合O-H官能团MIR伸缩振动模式的2级倍频(ν_(3-一维-NIR))、C-H官能团MIR伸缩振动模式(ν_(C-H-一维-MIR))和C-C官能团MIR伸缩振动模式(ν_(C-C-一维-MIR))的合频(ν_(4-一维-NIR))、C-H官能团MIR伸缩振动模式和CH_(3)官能团MIR对称伸缩振动模式(ν_(sCH3-一维-MIR))的合频(ν_(5-一维-NIR))、CH_(3)官能团MIR不对称伸缩振动模式(ν_(asCH3-一维-MIR))和CH_(2)官能团MIR不对伸缩振动模式(ν_(asCH2-一维-MIR))的合频(ν_(6-一维-NIR))。室温下,乙基纤维素分子官能团变化快慢顺序存在着一定的差异性。变化快慢顺序为,4250 cm^(-1)(ν_(1-2-二维-NIR))>4252 cm^(-1)(ν_(1-1-二维-NIR))>4248 cm^(-1)(ν_(1-3-二维-NIR)),6988 cm^(-1)(ν_(2-1-二维-NIR))>6976 cm^(-1)(ν_(2-2-二维-NIR)),11012 cm^(-1)(ν_(3-1-二维-NIR))>10998 cm^(-1)(ν_(3-2-二维-NIR)),4016 cm^(-1)(ν_(4-1-二维-NIR))>4012 cm^(-1)(ν_(4-2-二维-NIR)),5777 cm^(-1)(ν_(5-2-二维-NIR))>5774 cm^(-1)(ν_(5-3-二维-NIR))>5782 cm^(-1)(ν_(5-1-二维-NIR)),5895 cm^(-1)(ν_(6-2-二维-NIR))>5893 cm^(-1)(ν_(6-3-二维-NIR))>5900 cm^(-1)(ν_(6-1-二维-NIR))。三级漫反射NIR光谱组学(包括一维漫反射NIR光谱、一维原位漫反射NIR光谱和二维原位漫反射NIR光谱)技术可以有效开展乙基纤维素分子结构研究。
The molecular structure and average absorption frequency/intensity of ethyl cellulose were studied based on one-dimensional diffuse reflectance near-infrared(NIR)spectroscopy and one-dimensional in-situ diffuse reflectance NIR spectroscopy,respectively.Based on the two-dimensional,in-situ diffuse reflectance NIR spectroscopy with respect to the order of changes in the functional groups of ethyl cellulose molecules further is investigated.The experiment found that the NIR spectral absorption mode of the molecular structure of ethyl cellulose mainly includes CH_(3) functional group mid infrared(MIR)asymmetric bending vibration mode(δ_(asCH3-one-dimensional-MIR))two level frequency doubling(ν_(1-one-dimensional-NIR)),associated O-H functional group MIR stretching vibration mode(νO-H(associated)-one-dimensional-MIR)one level frequency doubling(ν_(2-one-dimensional-NIR)),associated O-H functional group MIR stretching vibration mode two level frequency doubling(ν_(3-one-dimensional-NIR)),C-H functional group MIR stretching vibration mode(ν_(C-H-one-dimensional-MIR))and C-C functional group MIR stretching vibration mode(ν_(C-C-one-dimensional-MIR))frequency combination(ν_(4-one-dimensional-NIR)),C-H functional group MIR stretching vibration mode and CH_(3) functional group MIR symmetric stretching vibration mode(ν_(sCH3-one-dimensional-MIR))frequency combination(ν_(5-one-dimensional-NIR)),CH_(3) functional group MIR asymmetric stretching vibration mode(ν_(asCH3-one-dimensional-MIR))and CH_(2) functional group MIR asymmetric stretching vibration mode(ν_(asCH2-one-dimensional-MIR))frequency combination(ν_(6-one-dimensional-NIR)).Under room temperature,there is a certain difference in the order of the change in the functional groups of ethyl cellulose molecules.The order of change speed is 4250 cm^(-1)(ν_(1-2-two-dimensional-NIR))>4252 cm^(-1)(ν_(1-1-two-dimensional-NIR))>4248 cm^(-1)(ν_(1-3-two-dimensional-NIR)),6988 cm^(-1)(ν_(2-1-two-dimensional-NIR))>6976 cm^(-1)(ν_(2-2-two-dimensional-NIR)),11012 cm^(-1)(ν_(3-1-two-dimensional-NIR))>10998 cm^(-1)(ν_(3-2-two-dimensional-NIR)),4016 cm^(-1)(ν_(4-1-two-dimensional-NIR))>4012 cm^(-1)(ν_(4-2-two-dimensional-NIR)),5777 cm^(-1)(ν_(5-2-two-dimensional-NIR))>5774 cm^(-1)(ν_(5-3-two-dimensional-NIR))>5782 cm^(-1)(ν_(5-1-two-dimensional-NIR))and 5895 cm^(-1)(ν_(6-2-two-dimensional-NIR))>5893 cm^(-1)(ν_(6-3-two-dimensional-NIR))>5900 cm^(-1)(ν_(6-1-two-dimensional-NIR)).The three-level diffuse reflectance NIR spectroscopy(including one-dimensional diffuse reflectance NIR spectroscopy,one-dimensional in-situ diffuse reflectance NIR spectroscopy and two-dimensional in-situ diffuse reflectance NIR spectroscopy)technology can effectively carry out the study of the molecular structure of ethyl cellulose.
作者
徐元媛
孔晓美
王春润
吉一帆
柴嘉欣
于宏伟
XU Yuanyuan;KONG Xiaomei;WANG Chunrun;JI Yifan;CHAI Jiaxin;YU Hongwei(College of Chemical Technology,Shijiazhuang University,Shijiazhuang Hebei 050035,China;School of Chemical and Pharmaceutical Engineering,Hebei University of Science and Technology,Shijiazhuang Hebei 050018,China;Anesthetic Technology Innovation Center of Hebei Province,Shijiazhuang Hebei 050035,China)
出处
《长沙大学学报》
2024年第5期53-60,共8页
Journal of Changsha University
基金
石家庄市麻醉药技术创新中心项目(石科[2019]34号)
河北省生物制药国际联合中心项目(冀科外函[2022]3号)。
关键词
乙基纤维素
一维漫反射近红外光谱
一维原位漫反射近红外光谱
二维原位漫反射近红外光谱
结构
ethyl cellulose
one-dimensional diffuse reflectance near infrared spectroscopy
one-dimensional in situ diffuse reflectance near infrared spectroscopy
two-dimensional in situ diffuse reflectance near infrared spectroscopy
structure
