Yanan Wang

Applying gel-type solid chlorine dioxide for the sustained release of chlorine dioxide has several shortcomings, such as no resistance to acid and alkali corrosion and poor mechanical properties. However, introducing quaternary ammonium, carboxyl, and amino groups into the hydrogel system can enhance its acid and alkali resistance. In this study, the effects of concentration of dry heat-modified starch, quaternized carboxymethyl cellulose, and chitin on the swelling behavior and mechanical properties of starch-based acid- and alkali-resistant hydrogels are investigated. The feasibility of the actual and predicted values of the tentative results is verified based on the response surface design to determine the optimal concentration ratio of acid- and alkali-resistant hydrogels. The results reveal that optimized process parameters are reliable. The maximum swelling ratio and compressive stress of the hydrogel are 5358.00% and 44.45 kPa, respectively, and its swelling behavior conforms to the pseudo second-order kinetic model. Thus, the present study can provide a new method of developing efficient starch-based chlorine dioxide hydrogels for the sustained release of chlorine dioxide.

Cost-effective, practical, and efficiently performing photosensitive resin composite materials are essential, as the current materials are expensive, lack better alternatives, and do not meet 3D printing standards. In this study, based on orthogonal experiments for photosensitive resin curing, we prepared a free-radical/cationic hybrid photosensitive UV cured resin (UVR) using acrylic ester and epoxy resin as the prepolymers, tripropylenediol diacrylate (TPGDA) as the active diluent, and triaryl sulfonium salt (I-160) and 2,2-dimethyl-α-hydroxy acetophenone (1173) as the photoinitiators, in the optimized formula of acrylic-ester:epoxy-resin:TPGDA:I-160:1173 = 37.5:37.5:20:2.5:2.5. Further, we investigated the effects of polyurethane acrylates (PUA) and Graphene oxide (GO) on the surface morphology, chemical structure, hydrophobicity, mechanical strength, and gelation rate of the hybrid resin. We observed that 20% PUA improved tensile strength to the maximum of 36.89 MPa from 16.42 MPa of the unmodified hybrid resin, whereas 1% GO reduced volume shrinkage to the minimum of 2.89% from 3.73% of the unmodified hybrid resin. These photosensitive resins with higher tensile strength and lower volume shrinkage can be used to synthesize high performance functional materials in the future.