Developing novel absorbent materials with both rapid absorption speed and efficient recovery of viscous crude oils presents an enticing prospect for crude cleanup and utilization. Herein, a strategy to synergistically reduce the viscosity of crude oil by using solar-assisted chemical emulsifiers is proposed, which can directly modify commercial sponges to achieve rapid adsorption and efficient recovery of crude oil by using modified commercial sponges. SiO2 nanofluids (SiO2 nfs), which acted as amphipathic chemical emulsifiers, were confirmed by the molecular dynamics results to have a strong physical action and emulsification effect on crude oil. Benefiting from the synergistic advantages of the SiO2 nfs and photo-thermal properties of the dopamine layer, compared to a commercial polyurethane sponge, the modified sponge exhibited a 10% increase in absorption capacity and a three order of magnitude increase in viscous crude oil absorption rate, and its crude oil recovery rate remained stable at over 90% after 10 cycles. This novel, modified sponge with high porosity, flame retardance, and durability has excellent potential for practical viscous crude oil spill cleanup applications with fast recovery and efficient cleanup under harsh conditions. This convenient and efficient manufacturing technique can be extended to other commercial sponges and is suitable for the large-scale production of new adsorbent materials.
The opportunity for the preparation of high-performance shape memory materials was brought about by the excellent mechanical properties of poly(lactic acid) (PLA). As the effect of crystallization on shape memory was still unclear, this brings constraints to the high-performance design of PLA. The PLA plates with different aggregation structure were prepared by three kinds of molding methods in this paper. The PLA plates were pre-stretched with a series of different strains above glass transition temperature (i.e., 70 °C). The recovery stress and ratio of the material were measured above stretching temperature (i.e., 80 °C). Prolonging of annealing time resulted in more perfect crystal structure and higher crystallinity. The crystal region acted as network nodes in shape memory PLA, and crystal region structure determined the shape memory performance. Based on the experimental results, the structural evolution of network nodes in shape memory PLA was established.