To address the depletion of non-renewable resources and align with the principles of green development, researchers increasingly turned to natural plant extracts to synthesise bio-based waterborne polyurethanes (BWPU) as a sustainable alternative to conventional petroleum-derived BWPUs. Although BWPU demonstrated low emissions and non-toxic characteristics, they still exhibited limitations in heat resistance and relatively reduced biodegradability. Thus, to enhance the overall performance of BWPU, sorbitan monooleate (SP) and quercetin (QC) were incorporated into the formulation of hybrid waterborne polyurethane (CWPU). As natural bio-based hybrid materials, QC and SP facilitated the formation of cross-linking networks and hydrogen bonds, enhancing intermolecular interactions and conformational stability in self-cross-linking CWPU. The research concentrated on investigating the chemical structure, mechanical properties, thermal characteristics, and biodegradability of CWPU. The results demonstrated that the introduction of QC constructed a dense cross-linking network, leading to an increase in elongation at the break of CWPU from 460 % to 864 %. Under the condition of 5 % weight loss (T5%), the thermal stability of CWPU was significantly enhanced, with the decomposition temperature increasing from 200 to 243 degrees C. In addition, after degradation in soil and in a 0.6 % lipase PBS buffer for 28 days, the weight of CWPU decreased to 53 % and 48 %, respectively. CWPU can optimise the utilisation of BWPU in biomedical and packaging applications, thereby contributing to innovations in environmentally friendly materials.

Cationic and anionic castor oil-based waterborne polyurethanes (C-WPU/A and C-WPU/C) have great potential for development in agriculture. However, it is still unclear whether these polyurethanes are harmful or toxic to soil fauna. Based on multilevel toxicity endpoints and transcriptomics, we investigated the effects of C-WPU/A and C-WPU/C on earthworms ( Eisenia fetida). ). The acute toxicity results showed that C-WPU/A was highly toxic to the earthworms, whereas C-WPU/C was nearly nontoxic. C-WPU/A significantly affected the body weight, burrowing ability and cocoon production rate of earthworms compared to C-WPU/C. After exposure to C-WPU/ A, the results showed accumulation of reactive oxygen species (ROS), abnormal peroxidase activity, and increased malondialdehyde levels. Additionally, more serious histopathological damage was observed in earthworms, such as epidermal damage, vacuolization, longitudinal muscle disorganization, and shedding of intestinal epidermal cells. At the cellular level, C-WPU/A induced more severe lysosomal damage, DNA damage and apoptosis than C-WPU/A. C-WPU/A made more differentially expressed genes and considerably more enriched pathways at the transcriptional level than C-WPU/C. These pathways are largely involved in cell membrane signaling, detoxification, and apoptosis. These results provide an important reference for elucidating the selective toxicity mechanisms of C-WPU/A and C-WPU/C in earthworms.