Abstract: In order to precisely measure the fineness of raw silk, some features of raw silk are analyzed. By use of Fresnel principle, diffractions caused by raw silk in different conditions are analyzed and simulated. Image data of the fineness of raw silk measured by CMOS image sensor is analyzed for obtaining precise result. Finally, some suggestions are proposed for photoelectric measuring the fineness of raw silk.
Abstract: As the single-end tenacity and elongation test of raw silk is required strongly by the raw silk customers instead of the skein test, some basic studies on this kind of testing means were made. The affecting factors on the distribution and statistical characteristics of the single-end tenacity and elongation test of raw silk were studied; and those factors include the draw speed and line density. Investigations in the article are hoped to bring useful help to the establishment of the testing method and testing standards of this kind of testing means.
Abstract: We examined the molecular orientation of paper and mechanical properties of prepared paper yarn by twisting strips of paper made from various ratios of mulberry bast and Manila hemp. The molecular orientation of paper in direction of the strip was highest for paper with a mulberry bast weight ratio of 30 wt% as measured by a microwave molecular orientation analyzer. In contrast, the paper yarn sample with a mulberry bast weight ratio of 100 wt% showed a low molecular orientation of paper in direction of the strip. For mechanical properties, paper yarn with mulberry bast weight ratio of 30 wt% had the highest strength and Young’s modulus and the lowest elongation. These results show that the mechanical properties of the paper yarn depend on the molecular orientation of the paper in direction of strip.
Abstract: Polyactic fibers have superior biodegradability, moisture absorption, resiliency and processibility and can be used in various fields especially in blood filtration. Polyactic can be melt blown into nonwoven fabrics. To predict the fiber diameter of the polyactic melt blown nonwoven fabric, the air drawing model of polyactic was established. The predicted fiber diameter tallies well with the measured fiber diameter. Computer simulations of the effects of the processing parameters on the fiber diameter were performed with the help of the air drawing model. The simulation results show that smaller polymer flow rate, larger initial air velocity and larger die-to-collector distance can all produce finer fibers while too large initial air velocity and too large die-to-collector distance contribute little to the air drawing of polyactic melts.
Abstract: In this paper, two hemicyanine dyes, DEASPI and DHEASPI-C1, were synthesized and used in acrylic fabrics as fluorescent dyes. The influence of the hydroxyl groups of dye molecules on the dyeing properties was analyzed, and the results showed that the exhaustion value and partition coefficient value decreased a lot when there were two hydroxyl groups attached to the end of dye molecule. The reflectance of the dyed acrylic fabrics with these two fluorescent dyes is higher than 100% in 600 - 700 nm. Moreover, the chromaticity of dyed acrylic fabric was calculated according to the EN-471 standard (2003).
Abstract: One hemicyanine dye, DHEASPBr-C2, has been synthesized in this paper and incorporated by doping to Polyvinyl Alcohol (PVA) to prepare the fluorescent nanofiber webs. SEM morphology and fluorescent properties of the electrospun webs were tested. Results showed that it is feasible to develop fluorescent orange nano-fibre webs from those incorporating solutions using electrospinning process (ESP) at room temperature. When measuring fibres selected from each electronspun webs in SEM images, the fibres diameters changed between 200 nm and 400 nm with the change of electrospinning technological parameters. The reflectance spectra of the electrospun webs showed that there are obvious sorption spectra in the range 380-550 nm and emission spectra in the range 560-700 nm, while the single-photon fluorescent emission spectra showed obvious fluorescent effect.
Abstract: Bamboo pulp fibers, made of fast grown bamboo, were the recycled and environment-friendly natural raw materials in the textile industry which particularly today was paid more attention to its good performance due to energy and environment crisis. Hyper branched polymer was attracted more study because of the vast potential application in the future. In this study, the fabrics were modified with the amino-terminated hyper branched polymer (HBP-NH2) by dipping method and anti-UV and anti-bacterial properties of the treated bamboo pulp fabric were investigated. The results showed that the treated bamboo fabric had good antibacterial properties, the bacteria reduction of S.aureus and E.coli were as high as 89% or more, and also remained at around 88% after 20 times washing. The UPF values were increased from 8.16 to 18.18 which improved the anti-UV property of bamboo fabric.
Abstract: In the present study, the influence of four 1-alkyl-3-methylimidazolium bromine ionic liquids (ILs), CnMImBr (n=4, 8, 12, 16) on the sorption of acid dyes by nylon fibers was investigated. The quantity of dye sorption at pH 5 and pH 7 was found to be greatly dependent on the concentrations of ILs and the length of alkyl groups in ILs. The quantity of dyes adsorbed by nylon increased in the presence of C8MImBr at all the concentrations employed, and in the presence of C12MImBr and C16MImBr at appropriate concentrations. The mechanism of the increase in dye sorption in the presence of ILs at appropriate concentrations is due to the existence of the new positively charged dyeing sites in nylon induced by the sorption of ILs on nylon. The further increasing concentrations of C12MImBr and C16MImBr decreased the extent of dye sorption, which can be explained by the greatly reduced quantity of free dyes in solution induced by the interaction between anionic dyes and cationic ILs in solution as well as the increasing aggregation of the complex of dyes and ILs.
Abstract: In this work, silk was grafted using dimethylaminoethyl methacrylate(DMAEMA) via activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) method to produce well controlled grafted silk in water aqueous. CuBr2 was used as catalyst, N, N, N’, N", N" -pentamethyldiethylenetriamine (PMDETA) was used as ligand, vitamin C was used as reducing agent. The effects of monomer concentration, the proportion of catalyst and ligand, the variety and the dosage of catalyst and reducing agent, grafting temperature and time on the silk grafting were discussed, and the optimal grafting technology was obtained. FT-IR characterization of the grafted silk indicated that DMAEMA was grafted onto the surface of silk. The whiteness and permeability to gas of grafted silk slightly decreased. And the moisture permeability of grafted silk nearly had no change. The wrinkle recovery angle of grafted silk dramatically increased.
Abstract: In order to develop silk underwear fabric with good anti-bacterial property, silk was grafted using 2-diethylaminoethyl methacrylate (DEAEMA) by atom transfer radical polymerization (ATRP) method. The amino groups and hydroxyl groups on the side chains of the silk fibroin was reacted with 2-bromoisobutyryl bromide (BriB-Br) to obtain efficient macroinitiator for ATRP. And the macroinitiator was grafted with DEAEMA in water/ethanol media using CuBr/N,N,N',N",N" -pentamethyldiethylenetriamine (PMDETA) as catalyst system. The effects of monomer concentration, the proportion of CuBr and PMDETA, grafting temperature and time on the silk grafting were discussed, and the optimal grafting technology was obtained. FT-IR characterization of the grafted silk showed a peak corresponding to DEAEMA, which indicated that DEAEMA was grafted onto the surface of silk. The quaternized grafted silk had good anti-bacterial property to S. aureus and E. coli. . And the bacteria repellency of the grafted silk had good washing durability.