Influence of Newly Organosolv Lignin-Based Interface Modifier on Mechanical and Thermal Properties, and Enzymatic Degradation of Polylactic Acid/Chitosan Biocomposites.

This article aimed to study the effects of chitosan fiber and a newly modifying agent, based on organosolv lignin, on mechanical and thermal performances and the enzymatic degradation of PLA/chitosan biocomposites. A newly modifying agent based on polyacrylic acid-grafted organosolv lignin (PAA-g-OSL) was synthesized via free radical copolymerization using t-butyl peroxide as the initiator. The biocomposites were prepared using an internal mixer and the hot-pressed method at various fiber loadings. The results demonstrate that the addition of chitosan fiber into PLA biocomposites remarkably decreases tensile strength and elongation at break. However, it improves the Young's modulus. The modified biocomposites clearly demonstrat an improvement in tensile strength by approximately 20%, with respect to the unmodified ones, upon the presence of PAA-g-OSL. Moreover, the thermal stability of the modified biocomposites was enhanced significantly, indicating the effectiveness of the thermal protective barrier of the lignin's aromatic structure belonging to the modifying agent during pyrolysis. In addition, a slower biodegradation rate was exhibited by the modified biocomposites, relative to the unmodified ones, that confirms the positive effects of their improved interfacial interaction, resulting in a decreased area that was degraded through enzyme hydrolysis.

Biological aspects of Myopopone castanea on it's prey Oryctes rhinoceros larvae.

Ants are social insects with some significant roles in the ecosystem, including acting as predators for various insect pests. Myopopone castanea ants is a predatorfor the larvae of Oryctes rhinoceros pest. The existence of a similar niche of life between M. castanea ants and O. rhinoceros larvae opens an excellent opportunity to utilize these ants as biological agents. The research was conducted to study some aspects biology of M. castanea so that later it can be applied to mass rearing of natural enemies in the laboratory. The study was conducted by maintaining 50 eggs of M. castanea ant. Then, the eggs placed on two pieces of decayed palm oil stem together with twenty individual worker ants and ten individual end instar larvae. It needs five replications for the experiment. The results showed that egg stadia length was 13.8 days. It found five instars within M. castanea ant larvae with varying lengths of each stage. It takes 17.2 days for worker ant pupae to go through stadia pupa and 17.9 days for female ant pupae. The survival rate of M. castanea ant life from eggs until imago is 56.4%, which means that from several groups of eggs laid by queen ants, only about half have succeeded in becoming ant imago.