Advanced Materials Research Vols. 332-334

Abstract: For protecting the environment, reducing pollution and saving energy, the technical process of silk degumming and sericin extracting was investigated in this paper. Boiling degumming and icing extracting mathod were adopted in the experiments. The optimal technological conditions of raw silk degumming and sericin extracting were obtained by using the orthogonal experimental design. The experimental results showed that the optimal technical parameters of silk degumming were the concentration of anhydrous sodium carbonate 2%, heating time 60min, bath ratio 1:30, as well as, for sericin extracting, they were pH value 7, temperature -24°C, freezing time 12h. On these conditions, the degumming loss percentage and the recovery rate were 26.1% and 75.5% respectively.

Abstract: In this study, Tencel staple fibers and PET low melting point fibers (LMPET) were blended to prepare composite nonwovens, with change of blending ratio of Tencel/LMPET, hot-baking time and temperature. By measurement of mechanical properties, the optimal parameters were found to become dressing covering material after analysis of experimental data, with adjustment of strength, breathability and flexibility of nonwovens. During membrane preparation, 3 % chitosan solution was exposed to UV ray for 1, 3, 5 minutes, and then manufactured into membrane by Freeze Dryer, in order to explore broken bond whether happened on chitosan structure and to further manage chitosan membrane degradation rate. With analysis of UV irradiation time influencing on membrane releasing, membrane at the same size was immersed in PBS for degradation test. According to mechanical and degradation results, it is showed that, 100 % Tencel nonwovens had better breathability and strength than that mixed with 30 % LMPET, and membrane had the most stable degradation rate after 5 min irradiation of chitosan solution. Finally, using most stable chitosan and Tencel nonwovens, Tencel/ Chitosan composite dressing fabric was compounded by coating.

Abstract: Poly(NIPAAm-co-AAc) hydrogels of different ratios were prepared by copolymerization and then modified with L-phenylalanine by amidation of carboxyl groups of acrylic acid. The structures of the hydrogels were identified by IR and the chiral separation experiments of hydrogels on D/L-phenylalanine were investigated. The results showed that the chiral hydrogels exhibited enantioselectivity for L-phenylalanine and the resolution capability increased with the rising of temperature and contents of L-phenylalanine groups.

Abstract: Microencapsulated n-octadecane (MicroC18) and doped with thermochromatic powders (TC-MicroC18) were prepared with melamine-formaldehyde (M-F) resin as the wall via in-situ polymerization. The chemical structure and thermal behavior of microcapsules were investigated using fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Experimental results show that 63 wt% n-C18 has been incorporated into microcapsules, and the obvious thermochromatic effect of TC-MicroC18 is displayed with temperature changing. The structure-properties of TC-MicroC18 also is discussed in detail from the aspect of molecular structure.

Abstract: Abstract. In this paper the hot steel work environment is simulated and a thermal manikin is utilized to evaluate the thermal adjusting effect of a cooling vest incorporated with PCM packs of gel. Two control modes of the thermal manikin, the constant energy input mode and the constant skin temperature mode are used respectively to evaluate the cooling vest’s thermal adjusting effect. The experiment demonstrates that the cooling vest can alleviate the manikin’s skin temperature. When the constant energy input control mode is used, the manikin’s body parts covered by PCMs have lower skin temperature than other body parts; When the constant skin temperature mode is used, the manikin’s chest and back part, followed by the abdomen and buttocks part have the highest energy cost.

Abstract: To develop an online monitoring and control system for textile dyeing process, an optical fibre sensing system was designed and developed. This paper focused on the measurement of reactive dye concentration in dyebath using the optical fibre sensing system. The optical fibre sensors were proved to be practicable to measure the dye concentration in the dye concentration range during the dyeing process. The measured data was compared with the calculated value, and the linear relation of absorbance to dye concentration was examined. The experiment included single dyes and mixture with double dyes. Dyes concentration measurement accuracy was discussed. The results show that the absorbance is proportional to dye concentration within actual dyeing concentration range. Measured data of dyes concentration well matched the calculated value. The limitations and the approach for improving this optical fibre sensing system were discussed.

Abstract: It is proposed a parallel Monte Carlo algorithm to simulate templated grain growth in sintering ceramics materials. The algorithm applies the general Potts model to treat the matrix as the discrete lattices for simulating the grain growth and there will be a number of lattices to be computed synchronously. The scheme is performed by CUDA GPU parallelization programming framework which is of much more feasibility and low cost comparing with the former conventional program. The most key point is that the parallel algorithm is of great temporal performance which means it takes less time to complete a simulation. The results of comparative experiments show that the algorithm is unquestionable effective while the other statistic numerical features of simulations are almost the same.

Abstract: AKD is an important internal size for paper pulp fiber. With recycled economy development, regenerated paper fiber becomes an important resource. In this paper, AKD is used as a modification aid by internal sizing method. It shows that the change of the dosage of AKD influences regenerated paper fiber Cobb value, but has no influence to paper surface strength. The proper pH value is from 7 to 9. The temperature has no influence to regenerated paper fiber Cobb value and paper surface strength. Appropriate modified starch is good for AKD modification fiber and increase of the surface strength of paper made from modified fiber by AKD. Amphoteric starch is better than cationic starch. Other added substances such as PEI, MPEI and PAE can improve the modification of paper fiber modified by AKD. So the adsorption of modified paper fiber decrease and the surface strength of paper modified fiber increase.

Abstract: Carbon nanotubes (CNTs) have been used in many materials due to their interesting properties. But CNTs do not disperse well within apolar polymer matrices such as polypropylene. Recently, polypropylene-graft-maleic anhydride (PP-g-MA) was used as a compatibilizer to improve the dispersion of CNTs within polymer. Disappointingly, the dispersion of CNTs was not expected. Here, utilizing 4-methylbenzenesulfonic acid as catalyst, PP-g-MA is chemically modified with phenol in dimethylbenzene. The resulting product (PP-g-PH) is characterized by the elemental analysis, fourier transform infrared spectra (FTIR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The dispersions of CNTs within PP-g-MA and PP-g-PH are studied.

Abstract: Wood-plastic composites (WPC), a fast growing class of material used by the furniture and building industry for its excellent mechanical performance and functionality. However, WPC is easily combust because the raw material of it, i.e. wood and plastic burns so easily which result in more fire dangers of WPC. Unfortunately, in the case of WPC, few researchers have carried out to reduce its flammability which still has a long way to go. In this paper, the current development of halogen-free flame retardant WPC at domestic and abroad was reviewed. Especially, the fire retarded WPC with phosphorus, nitrogen, boron, silicon and other flame retardant elements, the fire retarded mechanism, the problems, such as poor compatability, bad resistance to heat and limitation of wood adding quantity, and the solution to the problems were emphasized.