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Although supercritical carbon dioxide foaming technology has achieved significant advances in the fabrication of porous polymers, the slow adsorption of carbon dioxide and the high melt strength of engineering plastics make it difficult to foam. Herein, the “partition method” is used to divide block polyetherimide (PEI) into many tiny parts through the interconnected pores to realize the rapid adsorption of CO2molecules. Specifically, an adsorption capacity of 9.18 wt % for porous PEI was obtained at 35 °C for just 1 h which was considerably higher than that of 4.36 wt % for non-porous PEI. Then, PEI with a uniform and ordered hierarchically porous structure (micro- and nanoscale) was successfully prepared by external force-induced cell nucleation growth. Meanwhile, this treatment has little effect on the thermal properties of the polymer. This green strategy applies to other general plastics, for example, polystyrene, and paves the way for designing large-scale hierarchically porous components such as porous bearing cages, tissue engineering scaffolds, and thermal insulation foam.

Shape memory polyurethane (SMPU) with excellent mechanical properties holds significant application value in engineering. However, achieving high strength and toughness typically relies on hydrogen bonding for energy dissipation, which limits the application of such PUs due to their deformation temperature being below room temperature. Here, we introduce a rigid long-chain polyamide acid with a rich aromatic structure as a chain extender, combined with metal coordination, to develop a shape memory polyurethane with a phase transition temperature of 50 °C and outstanding mechanical performance. The presence of rigid segments of polyamic acid (PAA) and −COOH not only increases the rigidity of the polyurethane chains but also promotes the formation of hydrogen bonds and π–π conjugation, leading to physical cross-linking points and significant microphase separation, resulting in superior mechanical properties for PU-PAA. The dynamic bonding characteristics impart self-healing and solvent recyclability to PU-PAA. The coordination interactions enhance the cross-linking points, enabling PU-PAA-Eu to exhibit excellent shape fixation and recovery rates, as well as fluorescence properties. Additionally, due to the presence of −COOH, PU-PAA demonstrates remarkable adhesion to various metals. This work provides a strategy toward the development of high performance SMPU and holds promising potential for applications such as anticounterfeit coatings.

Blocks of phenolphthalein poly(ether sulfone) (PES‐C) were implanted with 110 keV protons in four doses: 1 × 1014, 5 × 1014, 2.5 × 1015, and 1.25 × 1016 ions/cm2. The structures of the pristine and implanted PES‐C blocks were characterized by FTIR–ATR and X‐ray photoelectron spectroscopy (XPS), whereas their friction and wear behavior were investigated with an M‐2000 friction and wear tester at room temperature in an ambient atmosphere. The results revealed that with an increased implantation dose, it took more time for the friction coefficient to become smaller and level off when the dose did not exceed 1016 ions/cm2. At the highest dose, 1.25 × 1016 ions/cm2, the friction coefficient started smaller but increased quickly and leveled off at a higher number. In addition, the wear rate first increased and then decreased. When the dose exceeded 1016 ions/cm2, the wear rate of the sample showed an obvious decrease. The FTIR–ATR spectra showed that partial degradation took place on the surface of PES‐C after proton implantation, and when the dose reached or exceeded 2.5 × 1015 ions/cm2, a new broad peak between 1600 and 1800 cm−1 appeared, showing that a carbon‐rich structure had formed on the sample surface. XPS analyses justified the FTIR–ATR results, including the formation of amorphous carbon and the partial degradation, which was responsible for the variety of friction and wear behaviors of PES‐C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3116–3119, 2006

Phenolphthalein poly(ether sulfone) (PES‐C) was implanted with 110 keV protons in four doses of 1 × 1014, 5 × 1014, 2.5 × 1015, and 1.25 × 1016 ions cm−2. The friction and wear properties of both implanted and unimplanted PES‐C were investigated with a THT07–135 high‐temperature tribometer against a steel ball. Results revealed that the friction coefficient and wear rate both decreased with increasing doses: especially when the dose reached 1.25 × 1016 ions cm−2, its wear rate decreased nearly two orders of magnitude. Scanning electron microscopy results revealed that the size of wear debris of unimplanted PES‐C was greater than that of the implanted one. The worn surface of unimplanted PES‐C showed plastic deformation, plastic flow, and adhesiveness, whereas the worn surface of the implanted one showed only some mild nicks. The carbon element distribution map revealed that much more carbon element transferred to the counterpart steel ball friction against the implanted PES‐C. The IR spectrum showed that partial degradation might occur when PES‐C was implanted with protons. Measurement of hardness revealed an increase with increasing doses. The reason for the increase might be the formation of carbon‐rich structures on the surface of the sample. From the above, conclusions can be drawn that the wear mechanisms of unimplanted samples were mainly related to adhesion, plastic deformation, and plastic flow, whereas that of implanted samples was mainly attributed to mild “three‐body” wear. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1043–1048, 2004