Cellulose tri-stearate (CTs) was synthesized employing trifluoroacetic anhydride (TFAA), stearic acid (SA), with microcrystal cellulose (MCC) and characterized with FT-IR and 1 H-NMR. The degree of substitution of CTs was determined by the traditional saponification method and 1 H-NMR. The thermal properties of CTs were investigated by the thermogravimetric analysis (TGA) under Ar flow in dynamic heating conditions. Thermal stability, activation energy, as well as the degradation mechanism of the decomposition process were revealed. The results showed that the thermal stability of CTs is superior to that of raw materials-MCC, and that the degradation of CTs in argon is a first-order weight loss; the initial decomposition temperature and the temperature corresponding to maximum degradation rate (T p ) increase with an increase in heating rate. The activation energy values were calculated with the Ozawa method, Coats-Redfern method and Kinssinger method, respectively. Analyses of experimental results suggest that the degradation mechanism 0.10 < α < 0.80 is F2 type, A3 for α < 0.1, and R3 for α > 0.80. The degradation mechanism of CTs in the whole conversion range is a complex mechanism, and is the combination of A3, F2 and R3.

A novel eco-friendly finishing agent of quaternary chitosan nanoparticles was prepared in two steps from a chitosan with low molecular weight. The water-soluble quaternary ammonium salt of chitosan, N-[(2-hydroxy-3-trimethylammonium)propyl] chitosan chloride (HTCC), was first synthesized in heterogeneous system by quaternization, and then HTCC was further prepared to nanoparticles via ionotropic gelation reaction in the presence of 1, 2, 3, 4-butane tetracarboxylic acid and sodium hypophosphite. The size distribution and morphology of the HTCC particles were characterized using a laser particle size analyzer and transmission electron microscope (TEM). When Antheraea pernyi (A. pernyi) silk fabric was treated with HTCC nanoparticles by using a conventional dip-pad-dry-cure process, the modified A. pernyi silk fabric demonstrated durable wrinkle-resistant property, shrinkage-resistant property and antimicrobial activities against Staphylococcus aureus and Escherichia coli, even after being exposed to 50 consecutive homelaundering conditions. However, the modification of A. pernyi silk fabric caused breaking strength loss, breaking elongation reduction and initial modulus rise to some extent.

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The surface hydrophilicity of thermoplastic rubber (TPR) is poor, and the effect of using it directly in oil well cement is not good. TPR was modified by different silane coupling agents, and the hydrophilicity of the modified TPR was studied by Fourier-transform infrared (FT-IR) spectroscopy and dispersion stability photography. The application effect of modified TPR in oil well cement slurry was also evaluated. The fracture surface morphology of TPR cement stone was observed by macrophotography and scanning electron microscopy (SEM). The results demonstrated that the hydrophilicity of TPR particles was improved after modification with silane coupling agent 3-methacryloxypropyltrimethoxysilane (KH570), and its application effect in cement slurry was excellent. Compared with the pure cement paste, the compressive strength of the cement paste with addition of TPR modified by KH570 was reduced, but the flexural strength and impact strength of the cement paste were effectively enhanced. Moreover, the modified TPR greatly improved the deformation capacity and decreased the elastic modulus of the cement paste. The modified TPR particles formed a plastic polymer network structure in the cement stone and penetrated the cement hydration products, filling in the cement paste to form a flexible structural center. Thus, it improved the mechanical properties and reduced the brittleness of cement paste.

Cellulose Oleate (CO) was synthesized by acylating cellulose in homogeneous system with p-toluenesulfonyl chloride (Tos-Cl) and oleic acid. The structure of CO was characterized by FT-IR, and degree of substitution (DS) of CO was determined by saponification method. Substituent distribution analysis was carried out with curve-fitting method, and the results indicated that acyl reaction of cellulose with oleic acid preferred to react at primary hydroxyl groups. The CO converted into films by casting. The mechanical properties of CO films were investigated. With the increase of DS, the tensile strength decreases gradually, but the tensile strain increases apparently.