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Different chemical treatment methods were employed to modify the surface of cotton stalk fibers, which were then utilized as fillers in composite materials. These treated fibers were incorporated into polylactic acid/polypropylene melt blends using the melt blending technique. Results indicated that increasing the surface roughness of cotton stalk fibers could enhance the overall mechanical properties of the composite materials, albeit potentially leading to poor fiber–matrix compatibility. Conversely, a smooth fiber surface was found to improve compatibility with polylactic acid, while Si-O-C silane coating increased fiber regularity and interfacial interaction with the matrix, thereby enhancing heat resistance. The mechanical properties and thermal stability of the composite materials made from alkali/silane-treated fibers exhibited the most significant improvement. Furthermore, better dispersion of fibers in the matrix and more regular fiber orientation were conducive to increasing the overall crystallinity of the composite materials. However, such fiber distribution was not favorable for enhancing impact resistance, although this drawback could be mitigated by increasing the surface roughness of the reinforcing fibers.

This paper describes an eco-friendly and efficient direct amidation of benzylamine and phenylacetic acid derivatives in the presence of 10 mol% NiCl2 as catalyst without any drying agent. For the different phenylacetic acid and benzylamine derivatives, the direct catalysed amidation gave moderate-to-excellent yields in toluene. The steric and electronic effects of substituent groups on the phenyl ring of acid were crucial to the yields of the direct amidation. The catalyst NiCl2 can be recycled three times without loss of activity.

A series of novel 13- to 15-member hydroxyproline-based macrocycles, which contain alkyl-alkyl ether and alkyl-aryl ether moieties, have been synthesized by the strategy of macrocyclization utilising azide-alkyne cycloaddition, Mitsunobu protocol and amide formation. Their anti-tumor activities towards A549, MDA-MB-231 and Hep G2 cells were screened in vitro by an MTT assay. The results indicated that 13-member macrocycle 33 containing alkene chain showed the best results, exhibiting the highest inhibitory effects towards lung cancer cell line A549, which was higher than that of the reference cisplatin (IC50 value = 2.55 µmol/L).