Six phase change materials (PCMs) were prepared by blending polyethylene glycol (PEG) with laponite powders (LP) at different ratios (PEG:LP, 100:0, 97:3, 96:4, 91:9, 88:12 and 85:15) under 100℃ firstly. A multi-layer composite consisting of a PCM loaded layer, a nano barrier layer and a protective layer was used to hold PEG/LP PCMs. SEM was used to observe the morphological structure of multi-layer composites containing PEG/LP composites. DSC revealed the melting temperature, the cooling temperature and the enthalpy of PEG and laponite as PCM. The thermal insulation of all the composites containing PEG/LP was evaluated under 78℃. The results gave that the multi-layer composite containing PCM was obtained and a better adhesion of between the PCM loaded layer, the nano barrier layer and the protective layer was found. LP functionalized as a nucleating agent to accelerate the crystallization of PEG and 15wt% LP in PCM resulted in a disordered PEG molecular. The composites with more laponite had the higher thermal insulation and highest value reached 0.25.
The conformational changes of hydroxyl groups aﬀect the structure behavior directly, it is important to study the structure properties of cellulose II. In order to explore them, the molecular structure was investigated by using the molecular dynamics simulation at diﬀerent temperature. The results indicate that the initial model and the force ﬁeld are reasonable. With the temperature raising, the standard deviations of the glycosidic torsion angle φ of center and origin chains increase 56.56% and 38.63%respectively. Likewise, the standard deviations of torsional angle ψ of the center chains and origin chains increase 32.89% and 34.91% respectively. The increase of standard deviations of these torsional angles promote the ﬂexibility of the hydroxyl groups and further correspond to the reduction of the hydrogen bond probability. The distance and probability of intersheet hydrogen bond O2c-Hc. . . O6c’ are the shortest and largest respectively at diﬀerent temperature. This is related to only one peak of the dihedral angle τ2 in the center chain, even if the peak decreases with temperature increasing. The large ﬂuctuation of the intrachain hydrogen bond O3-H. . . O5 in probability and distance is directly related to the glycosidic torsion angle φ rather than the dihedral angle τ3. However, the intersheet hydrogen bond O6c-Hc. . . O6o’ is very unstable and corresponds to the minimum steric hindrance for dihedral angle τ6. According to the probability, distance and angle of diﬀerent hydrogen bond types, the intrasheet hydrogen bond of cellulose II crystal is more stable than that intersheet and intrachain hydrogen bonds at diﬀerent temperature.
As a common disease in the elderly, the research on knee arthritis is mostly clinical treatment, but the research on functional health care pants for the daily health care of knee osteoarthritis patients is less. In view of this phenomenon, this paper explores the function of the health pants through the interviews of experts and the questionnaire survey of patients, and analyzes the weight of the function demand. Aiming at the ﬁve functional requirements with large weight, the fabric was screened, tested and analyzed by grey correlation degree. According to the analysis results, choose the fabric with better function and choose diﬀerent tissues according to diﬀerent parts, so as to design a kind of health care pants for knee arthritis to meet the needs of health care and comfort.
The characteristics of a weft knitted fabric made of new cotton non-twisted hollow yarn targeting an inner wear product were investigated. The weight, thickness, thermal characteristics, tensile, shear properties, bending properties and surface properties of the knitted fabric and four commercially available inner wear fabrics were measured using a KES-FB system. The measured properties were examined to examine the usefulness of the new fabric for inner wear. Fabric characteristics were compared in a multiple comparison test. The knitted fabric made of non-twisted hollow yarn is lighter and fuller than commercially available inner wear fabrics. The shear stiﬀness and bending rigidities of the knitted fabric were similar or lower than ones of commercially available cotton inner wear fabrics. The surface properties of the new fabric were similar to ones of commercially available inner wear fabrics. The fabric also has a lower Q-max value (the peak value of heat transferred), lower thermal conductivity, and higher heat retention rate and is therefore warmer than the commercially available fabrics. It is thus considered that knitted fabric made of new cotton non-twisted hollow yarn is suitable for inner wear.
Wet electrospinning is a convenient and versatile method to produce nanoﬁbers. When adding an active agent into the bath solution, functional ﬁbers may be fabricated in the ﬁber-forming process. In this paper, the spinnability of PA6/CS-NPs hybrid nanoﬁber ﬁlaments was studied which might obtain antibacterial activity. Three dispersants were selected, including span-80 and tween-80 (ST) (1/1, w/w), sodium polyacrylate (PAAS) and methyl cellulose (MC) to improve the dispersibility of the chitosan nanoparticles (CS-NPs) in the Peregal O aqueous solution. The mixture of ST was ﬁnally determined to be applied in the bath solution mainly because the agglomeration of CS-NPs could be largely reduced and the suspension of CS-NPs be maintained comparatively stable, and the continuous spinning time was longer than the others. When ST was added into the bath solution to fabricate the ﬁbers, by varying the compositions of the bath solution, including concentrations of the CS-NPs and ST, the morphologies of PA6/CS-NPs ﬁbers were investigated. When the composition of the bath solution was 0.2 wt.% ST and 0.4 wt.% CS-NPs, the maximum number of CS-NPs could be observed on the surface of the nanoﬁbers. Compared to the pure PA6 nanoﬁber ﬁlaments, the mechanical properties of the PA6/CS-NPs hybrid nanoﬁber ﬁlaments would be weakened.