We demonstrated a facile and efficient approach for the fabrication of few-layer graphene in DMF and graphite nanosheets in water with the assistance of high pressure homogenization. This work provides a physical perspective for understanding the exfoliation of other layered materials in liquid phase exfoliation.

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Sodium lignosulfonate (SL) has great potential to access lignosulfonate-based functional materials with high value. In this work, experiments and dissipative particle dynamics (DPD) simulations were employed to investigate the effect of sodium benzenesulfonate (SBS) on the preparation of lignosulfonate-based spherical micelles. DPD simulations and scanning transmission electron microscopy (STEM) analysis showed that independent sodium lignosulfonate (SL) molecules with various molecular weights only led to the formation of irregular and unordered aggregates in ethanol. Moreover, irregular and unordered SL aggregates with larger sizes were also obtained with increasing the molecular weight of SL. DPD simulations indicated that SL molecules with different molecular weights were able to self-assemble into various regularly spherical micelles in the presence of SBS, sodium p-methylbenzene benzenesulfonate, or sodium p-ethylbenzene benzenesulfonate. The SBS-assisted formation of lignosulfonate-based spherical micelles was attributed to the native formation of the SBS spherical base, and less than 10% of water was more beneficial to prepare the spherical micelles. STEM and cryo-scanning electron microscopy (cryo-SEM) analyses demonstrated that the SBS-assisted preparation of lignosulfonate-based spherical micelles with regular and ordered structures could be achieved using experimental methods.

Stimuli-responsive polymer materials have potential uses in drug delivery, tissue engineering, bioreactors, and cell-surface adhesion control. Temperatureresponsive surfaces of triblock copolymers of poly(N-isopropylacrylamide)-b-polycaprolactone-b-poly(N-isopropylacrylamide) (P(NIPAAm)-b-PCL-b-P(NIPAAm)) were fabricated via atom transfer radical polymerization (ATRP). At 37 °C [above the lower critical solution temperature (LCST) of NIPAAm of 32 °C], the seeded cells adhered on the surface of the triblock copolymer, while below the LCST the cells detached from the surface spontaneously. P(NIPAAm) acted as the thermoresponsive segments of the triblock copolymer for control of cell adhesion and detachment. The thermosensitive copolymers are potentially useful as stimuli-responsive adhesion modifiers for cells in biomedical fields.

Flow mark defects (FMs) worsen surface esthetics and mechanical properties of injection‐molded polypropylene (PP). In this work, experiments and dissipative particle dynamic (DPD) simulations were used to investigate the effect of dynamically vulcanized polyolefin elastomer (POE) on FMs of injection‐molded PP. Significant FMs reduction was achieved by dynamically vulcanized POE. DPD simulations indicated that POE molecules were randomly distributed in the PP, while dynamic vulcanization led to the formation of elastomeric quasi‐clusters, and these quasi‐clusters were able to reduce FMs. Both DPD simulations and scanning electron microscopy results showed that more agglomerates with longer and irregular shapes formed with longer vulcanization time and more initiators. The formation of too many agglomerates resulted in different pock surface defects. Dynamically vulcanized POE produced at optimal reaction conditions did not affect the tensile strength, tensile modulus, flexural strength, and flexural modulus, while breaking elongation and notched Izod impact strength of injection‐molded PP decreased slightly. This work suggests that the addition of dynamically vulcanized POE may be a promising way to reduce FMs of injection‐molded PP.