Leafhopper-inspired reversibly switchable antireflection coating with sugar apple-like structure arrays.

Optical coatings with reversibly tunable antireflective characteristics hold a tremendous potential for next generation optical energy-related applications. Bioinpsired by the camouflage behavior of small yellow leafhoppers, silica hollow sphere/shape memory polymer composites are self-assembled using a non-lithography-based approach. The average visible transmittance of the as-patterned hierarchical structure array-covered substrate is increased by ca. 6.3% at normal incident, and even improved by more than 20% for an incident angle of 75°. Interestingly, the broadband omnidirectional antireflection performance can be reversibly erased and recovered by applying external stimuli under ambient conditions. To gain a better understanding, its reversibility, mechanical robustness, and the structure-shape effect on the antireflective properties are systematically investigated in this research.

Development of a novel resin for provisional prostheses using hyperbranched polyurethane acrylate and triethylene glycol dimethacrylate - An in vitro study.

PURPOSE: To develop a novel resin for provisional prostheses using hyperbranched polyurethane acrylate (HBPUA) and triethylene glycol dimethacrylate (TEGDMA) with promising mechanical properties and low volumetric shrinkage. METHODS: Four groups including TIH3-0 (100 wt% TEGDMA), TIH3-30 (30 wt% HBPUA + 70 wt% TEGDMA), TIH3-60 (60 wt% HBPUA + 40 wt% TEGDMA), and TB-60 (60 wt% bisphenol A-glycidyl dimethacrylate + 40 wt% TEGDMA) were prepared and commercial Luxatemp (DMG) was used for comparison. Fourier transform infrared spectroscopy and gel permeation chromatography were used for material characterization. Mechanical properties including microhardness, flexural strength, flexural modulus, and load energy were measured before and after water immersion. Physical properties measurement included weight changes, solubility, water absorption, surface hydrophobicity, and volumetric shrinkage. Finally, biocompatibility was evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. RESULTS: The number- and weight-average molecular weights of the HBPUA were approximately 870 and 1480, respectively. The addition of HBPUA to TEGDMA increased the mechanical strength considerably. Although the weight changes and water absorption of TIH3-60 were higher than those of Luxatemp, the microhardness, flexural strength, flexural modulus, load energy, solubility, shrinkage, and biocompatibility of TIH3-60 were either comparable or superior to those of Luxatemp. CONCLUSION: Based on the findings of the present study, TIH3-60 has potential for development as a new provisional material.

Thin-Film Coated Plastic Wrap for Food Packaging.

In this study, the antimicrobial property and food package capability of polymethylpentene (PMP) substrate with silicon oxdie (SiOx) and organic silicon (SiCxHy) stacked layers deposited by an inductively coupled plasma chemical vapor deposition system were investigated. The experimental results show that the stacked pair number of SiOx/SiCxHy on PMP is limited to three pairs, beyond which the films will crack and cause package failure. The three-pair SiOx/SiCxHy on PMP shows a low water vapor transmission rate of 0.57 g/m²/day and a high water contact angle of 102°. Three-pair thin-film coated PMP demonstrates no microbe adhesion and exhibits antibacterial properties within 24 h. Food shelf life testing performed at 28 °C and 80% humidity reports that the three-pair thin-film coated PMP can enhance the food shelf-life to 120 h. The results indicate that the silicon-based thin film may be a promising material for antibacterial food packaging applications to extend the shelf-life of food products.