The preparation of multifunctional polymer materials from natural renewable resources via a simple method meets ever-expanding practical applications and matches sustainable development strategies. We synthesized a multifunctional polymer with a dual-dynamic three-dimensional (3D) crosslinked network of hydrogen bonds and dynamic imine bonds from epoxy soybean oil and vanillin via a simple preparation process. The as-prepared polymers have controllable mechanical strength between ultrahigh stretchability (strain at break: over 2800%) and rigidity (bending strength: 25.51 ± 0.27 MPa with a strain at break of approximately 2%) via varying imine bonds to readily tailored. They can be used as reusable adhesive. The highly dynamic nature of the hydrogen and imine bonds allows the damaged polymer to self-heal, and it can be re-recycled multiple times. The healed and recycled polymer regains most of its mechanical strength. The polymer exhibits both permanent and temporary shape memory at the same temperature via solid state plasticity, i.e., topological polymer network rearrangement resulting from dynamic bond exchange. Furthermore, our polymers can be used to prepare conductive adhesives/composites that are self-healing, recyclable, and re-shapable.

With rising environmental concerns and depletion of petrochemical resources, biomass-based chemicals have been paid more attention. Polyvinyl chloride (PVC) plasticizers derived from biomass resources (vegetable oil, cardanol, vegetable fatty acid, glycerol and citric acid) have been widely studied to replace petroleum-based o-phthalate plasticizers. These bio-based plasticizers mainly include epoxidized plasticizer, polyester plasticizer, macromolecular plasticizer, flame retardant plasticizer, citric acid ester plasticizer, glyceryl ester plasticizer and internal plasticizer. Bio-based plasticizers with the advantages of renewability, degradability, hypotoxicity, excellent solvent resistant extraction and plasticizing performances make them potential to replace o-phthalate plasticizers partially or totally. In this review, we classify different types of bio-based plasticizers according to their chemical structure and function, and highlight recent advances in multifunctional applications of bio-based plasticizers in PVC products. This study will increase the interest of researchers in bio-based plasticizers and the development of new ideas in this field.

Internally plasticized poly(vinyl chloride) (PVC) materials are investigated via grafting of propargyl ether cardanol (PEC). The chemical structure of the materials was studied by FT-IR and ¹H NMR. The performace of the obtained internally plasticized PVC materials was also investigated with TGA, DSC and leaching tests. The results showed that grafting of propargyl ether cardanol (PEC) on PVC increased the free volume and distance of PVC chains, which efficiently decreased the glass transition temperature (T_g). No migration was found in the leaching tests for internally plasticized PVC films compared with plasticized PVC materials with commercial plasticizer dioctyl phthalate (DOP). The internal plasticization mechanism was also disscussed according to lubrication theory and free volume theory. This work provides a meaningful strategy for designing no-migration PVC materials by introducing cardanol groups as branched chains.