Thermo-Responsive Behavior of Mixed Aqueous Solution of Hydrophilic Polymer with Pendant Phosphorylcholine Group and Poly(Acrylic Acid)

A mixed aqueous solution of hydrophilic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and poly(acrylic acid) (PAAc) becomes cloudy under acidic conditions at room temperature. The pendant carboxylic acid groups in PAAc form hydrogen bonds with the ester and phosphate groups in PMPC. While the polymers aggregate under acidic conditions, neither one associate under basic conditions because of the deprotonation of the pendant carboxy groups in PAAc. We observed that the interpolymer complex formed from PMPC, and PAAc was dissociated in aqueous solutions with increasing temperature, which is an upper critical solution temperature behavior. With increasing temperature, the molecular motion increased to dissociate the interpolymer complex. The phase transition temperature increased with increasing polymer and salt concentrations, and with decreasing pH.

Electrospun cationic nanofiber membranes for adsorption and determination of Cr(vi) in aqueous solution: adsorption characteristics and discoloration mechanisms

Cationic nanofiber membranes are prepared by electrospinning mixed aqueous solution of a cationic polycondensate (CP) and PVA. Apart from being a highly efficient Cr(vi) adsorbent, it can also serve as a convenient method for Cr(vi) determination.

Glycerin/NaOH Aqueous Solution as a Green Solvent System for Dissolution of Cellulose

Dissolving cellulose in water-based green solvent systems is highly desired for further industrial applications. The green solvent glycerin—which contains hydrogen-bonding acceptors—was used together with NaOH and water to dissolve cellulose. This mixed aqueous solution of NaOH and glycerin was employed as the new green solvent system for three celluloses with different degree of polymerization. FTIR (Fourier-transform infrared), XRD (X-ray diffractometer) and TGA (thermogravimetric analysis) were used to characterize the difference between cellulose before and after regenerated by HCl. A UbbeloHde viscometer was used to measure the molecule weight of three different kinds of cellulose with the polymerization degree of 550, 600 and 1120. This solvent system is useful to dissolve cellulose with averaged molecule weight up to 2.08 × 105 g/mol.

Effect of Alkaline Copper Quaternary Type D on Color Retention, Mold Resistance, and Surface Physicochemical Characterization of Neosinocalamus affinis Bamboo

The effect of alkaline copper quaternary type D (ACQ-D) treatment on color retention, mold resistance, and surface physicochemical characterization of Neosinocalamus affinis bamboo was analyzed. The results showed that a treatment of 0.25 percent ACQ-D solution combined with pretreatment of potassium hydroxide and sodium dodecyl sulfate mixed aqueous solution can achieve a desired green color on the bamboo surface. The mold test result revealed that the treated bamboo samples had better mold resistance than samples only treated with a mold inhibitor. The thermogravimetric–Fourier-transform infrared spectroscopy analysis of the treated and the control samples indicated that the chemical structure of the surface was slightly modified, e.g., silicon was almost completely removed, which enhanced liquid permeability. The dilute ACQ-D solution combined with a proper pretreatment process could retain the favorable green color of bamboo and also improve mold resistance by slightly modifying the surface chemistry.

Study on the Electrospinning of Gelatin/Pullulan Composite Nanofibers

In this study, gelatin and pullulan were successfully prepared as a novel type of protein–polysaccharide composite nanofibrous membrane by electrospinning at room temperature with deionized water as the solvent. The effects of gelatin content on the properties of the solution, as well as the morphology of the resultant nanofibers, were investigated. Scanning electron microscopy (SEM) was utilized to observe the surface morphology. Fourier transform infrared spectroscopy (FTIR) was used to study the interaction between gelatin and pullulan. Incorporation of pullulan with gelatin will improve the spinnability of the mixed aqueous solution due to lower surface tension. Moreover, the conductivity of the solution had a greater effect on the fiber diameters, and the as-spun fibers became thinner as the viscosity and the surface tension increased due to the addition of the polyelectrolyte gelatin. Gelatin and pullulan formed hydrogen bonds, and the intermolecular hydrogen bonds increased while the intramolecular hydrogen bond decreased, which resulted in better mechanical properties. The electrospun gelatin/pullulan nanofibers could mimic both the structure and the composition of the extracellular matrix, and thus could be applied in tissue engineering.

Preparation of a Kind of Non-Woven Viscose Colour Absorbing Material and Research of its Colour Absorption Properties

A non-woven viscose material was modified with self-made cationic gelatin protein auxiliary by the padding process. The material prepared was then used as an environmentally friendly colour absorbent for the decolourisation of dye wastewater. The effects of the sodium hydroxide swelling pretreatment process and cationic padding modification process on the colour absorption and decolourisation rate were discussed. Moreover an optimal preparation process for the colour-absorbing material was determined. This was as follows: In order to make the non-woven viscose material swell and improve the subsequent modification effect, first the non-woven viscose material was pretreated with an aqueous solution containing 50 g/l of sodium hydroxide, at room temperature, for 5 min. Then the material was padded in a mixed aqueous solution containing 80 g/l of cationic gelatin and 18 g/l of sodium hydroxide by means of a laboratory padder with two dips and two nips. After treatment, the material was dried and steamed for 4 min. Lastly the material was washed with water and dried. The results show that the colour-absorbing material prepared by this process has the advantages of a high colour absorption rate and high decolourisation percentage. And it could be applied to the decolourisation of printing and dyeing wastewater, or to prevent washed off dyestuff staining on light colour clothes in the process of laundry.