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Lanthanum phenylphosphonate (LaHPP) was synthesized through solution reflux method with a hydrothermal reaction. The synergistic effect of decabromodiphenyl oxide (DBDPO) and LaHPP on thermal stability and flame retardancy of polycarbonate (PC) were investigated. Transmission electron microscope graphs showed that LaHPP dispersed well in the PC matrix. Thermogravimetric analyses indicated that the addition of LaHPP into PC/DBDPO composites led to better thermal stability. An appropriate content (1 wt%) of LaHPP could improve the UL94 rating (from V-2 to V-0) and limiting oxygen index value (from 32.8 to 40.5%) dramatically, and also brought an effective reduction in peak heat release rate and smoke release rate in cone calorimeter. Investigation of gaseous pyrolysis products and char residues demonstrated that LaHPP promoted the formation of more compact and solid chars, which acted as physical barriers to inhibit heat and oxygen transfer. The inside char layers also provided more space and time for DBDPO to play its flame retardant role in gaseous phases. POLYM.

First principle of preparing slippery lyophobicity was the low surface-free energy, and the dynamic wettability was related to the kinematic viscosity.

This study investigates the effect of nanocrystalline cellulose (NCC) and polyethylene glycol (PEG) on the hydrolytic degradation behavior of poly(lactic acid) (PLA) bio-nanocomposites compared with that of neat PLA, under specific environmental condition, namely at 37 C in a pH 7.4 phosphate buffer medium for a time period up to 60 days. The water absorption, mass loss, molecular weight, and the morphologies of nanocomposites before and after degradation were explored. Thermogravimetric analysis (TGA) was used to study the thermal decomposition of the PLA/NCC/PEG nanocomposites before and after degradation. The results showed that the presence of hydrophilic NCC and PEG significantly accelerated the hydrolytic degradation of PLA, which was related to the rapid dissolution of PEG causing easy access of water molecules to the composites and initiating fast hydrolytic chain scission of PLA. The thermal degradation temperatures of the nanocomposites slightly decreased due to the poor thermal stability of NCC in comparison with that of the neat PLA. After degradation, the thermal stability of the separated PLA from nanocomposites significantly decreased because the molecular decreased during the hydrolytic process.