Advanced Materials Research Vols. 284-286

Abstract: Oleoyl chloride was synthesized by oleic acid and thionyl dichloride (SOCl₂), and then reacted with chitosan in dichloromethane to obtain the oleoyl chitosan. Novel water-soluble oleoyl acetyl chitosan (OACh) was synthesized using oleoyl chloride reacted with acetic anhydride in pyridine. The chemical structure of the OACh was characterized by FT-IR, ¹H and ¹³C NMR. There existed the peaks at 1743.9 cm^-1 (C=O) and 1658.1 cm^-1(C=C) in FT-IR spectrum, and the peaks at 170.8, 171.6 and 172.5 ppm which were assigned to the C=O of the oleoyl and acetyl groups in ¹³C NMR spectrum. The results indicated that OACh had oleoyl as hydrophobic moieties and acetyl as hydrophilic moieties.

Abstract: The biodegradable composite films were prepared from bagasse microcrystalline cellulose as filler and polylactic acid (PLA) as polymeric matrix. The crystallinity, the tensile properties and the thermal properties of the composites were tested. The results show that the tensile properties and thermal properties were improved with the addition of bagasse microcrystalline cellulose. When bagasse microcrystalline cellulose mass fraction was 5%, the initial decomposition temperature was raised by 30.73°C, and the tensile strength increased by 50.98%, and the elongation at break increased by 16.25% compared to those of pure PLA.

Abstract: A kind of endurant antibacterial PE films were prepared by using Nano-TiO₂ modified by JH-3112 silane or titanate coupling agents. The optimum amount of modified TiO₂ in PE substrate was concluded from the comprehensive performances of TiO₂/PE films. The antibacterial properties of Nano-TiO₂ and Nano-TiO₂/PE films were studied respectively. It was indicated that antibacterial abilities of Nano-TiO₂/PE films dramatically increased as comparing with PE films without TiO₂.

Abstract: Type I collagen was isolated from calf skin and its assembly on PVA film induced by glutaraldehyde vapor was investigated. It was found that the collagen molecules were firstly orientationally assembled into collagen fibers under the inducement of glutaraldehyde vapor. Then the collagen fibers could be further aggregated into novel network structure in proper conditions of the induced reaction. The morphology of the assembled collagen fibers was depended on induced time and concentration of collagen. The network arrangement could be obtained after being induced for 72h when collagen concentration was 2.5mg/ml. At higher concentration of collagen (5 mg/ml), the collagen fibers with larger dimension were obtained, but the growth of fibers was almost in one direction.

Abstract: In this paper, the effective nanocompoties (EFNCs) as drug carriers are prepared by grafting reaction of cationic chitosan (CS) and anionic tripolyphosphate (TPP) to encapsulate cancer therapeutic agents such as berberine (BB), KCY-24B…etc. These EFNCs were featured by ultra violet–visible-near infrared spectrophotometer (UV-VIS-NIR spectrophotometer), fourier transform infrared spectrophotometer (FT-IR), zetasizer, transmission electron microscope (TEM) and field-emission scanning electron microscope (FESEM). So we can obtain here the synthetic method, characterization, and functionality of these effective nanoparticles.

Abstract: High-temperature resistant epoxy adhesives cured under room-temperature becomes more and more important in many industries such as aerospace and aviation, the locomotive and diesel, etc. In this paper three self-made amine-based mannich-amide was mixed with E-44 epoxy resin under the same technological parameters, and the epoxy adhesives cured by the three amine-based mannich-amides under room-temperature are tested by FTIR, TGA and DMA. Results of TGA show a quicker drop in weight occurrence within 150-250°C for epoxy networks cured by multiamine-based mannich amides than the long-chain alkyl one. Results of FTIR show completely curing of epoxy adhesives cured by mannich amides under room temperature and the height of absorption band 1502cm^-1 (C-N) is much lower after 12h under 150°C,200°C atmosphere than 25°C. Results of DMA show that the Tg determined by DMA has an order EP AN2(89.9°C) >EP AN1(89.7°C)>EP AN3(80.8°C). In the rest results of DMA, the EP-AN3 system has the biggest storage modulus (E’) within 100-150°C while the EP-AN3 system has the smallest loss modulus(E”) within 100-150°C. As a whole, the epoxy adhesives cured by AN3 under room-temperature have the best high temperature resistance.

Abstract: “Water-in-water” emulsions of hydrophobically associating cationic polyacrylamide (HACPAM) with both cationic groups (methacrylatoethyl trimethyl ammonium chloride, DMC) and hydrophobic groups (n-butyl acrylate, BA) were synthesized by dispersion polymerization. The structure of the copolymer was confirmed by FTIR and 1HNMR. The prepared “water-in-water” emulsions possessed high solid content, low viscosity, good stability and solubility. An image analyzer photographed the size of the emulsion particles. The polymerization behaviors with varying concentrations of acrylamide, DMC, BA, stabilizer and reaction time were investigated. Appropriate concentrations of monomer, BA and DMC for stable dispersion system were in the scope of 10~15 wt%, 0.025 ~ 0.15 wt% and 1~ 4 wt%, respectively. The dynamic drainage experiment results show that the HACPAM “water-in-water” emulsions can be directly used as retention aid and obviously improve the retention efficiency of bleached broad-leaved pulp.

Abstract: In the present study, three BMP-2 (bone morphogenetic protein-2) micropatterns were produced on polystyrene (PS) surface by microcontact printing in order to investigate the effect of protein micropattern on biomaterials surface on human chondrocytes behavior. The excellent BMP-2 micropatterns from fluorescent observation were successfully obtained. Cell adhesion and immunohistochemical assay were utilized to explore cell behavior. The results indicated that the protein micropatterns have significant influence on cell adhesion, spread, alignment and protein expression. The cells preferentially adhered on protein micropattern zones. The cells tend to spread towards micropattern direction, leading to better spread. The spread cells could excreted more type II and VI collagen than that of non-spread or poor-spread cells. The results of this paper suggested that extracellular matrix (ECM) protein micropatterns can effectively regulate human chondrocytes behavior, which may be helpful for development of new cartilage tissue.

Abstract: The synthesis of a glycodendrimer by incorporating repetitive mannoside units onto a glucoside core was completed in order to prepare a multivalent probe to study fundamental carbohydrate-protein interactions.

Abstract: Electrofusion joint is used widely for PE pipes; the quality of the joint influences the safety of gas distribution system. Proven and reliable NDT technology of the joint is immature. The attenuation of ultrasound in PE is higher than for metals. Defects Include voids, cracks, bad fusion interfaces, dislocations of heating wires, could find be ultrasonic phased array testing. Examination time, surface of specimen, transducer, calibration block, resolution, examination range and couplant are recommend.