塑料先进制造加工——王琪团队研究工作进展OA

Significance Plastics,characterized by their excellent overall properties,are widely used in aerospace,transportation,new energy,electronics and electrical engineering,construction,agriculture,and medical care.They serve as essential foundational materials as well as advanced engineering materials.China's plastic product output reached 79.2 million tons in 2025,ranking first globally.Plastics require processing before they are formed into final products.Due to the covalent bonds,multilevel structures,viscoelasticity,and soft matter characteristics of polymeric materials,the final structure and properties of plastic products depend much more significantly on processing conditions than those of other materials.Plas-tic processing is not merely a shaping technology;rather,it represents a scientific discipline dedicated to designing and achieving the desired structures and properties of polymeric materials.With the rapid advancement of modern science,technology,and the national economy,advanced plastic manufacturing and processing,as a critical component of China's manufacturing industry,face new scientific frontiers and major national demands.These challenges include the high-performance and functional upgrading of plastic products to meet the requirements of high-end manufacturing,the high-value and efficient recycling of waste plastics to reduce environmental pollution and raise resource recycling,the devel-opment of non-petroleum-based plastics to ensure raw material security,the efficient utilization of natural biomass to optimize resource utiliza-tion,and the development of halogen-free flame-retardant plastics to enhance fire safety.Addressing these challenges requires the urgent develop-ment of new theories,technologies,and equipment for advanced plastic manufacturing and processing. Progress For decades,the team led by Academician Wang Qi at Sichuan University conducted systematic and in-depth research that addressed academic frontiers and key national economic demands in plastic processing,with a focus on high performance,multifunctionality,lightweight design,precision,and ecological sustainability.The team creatively solved several world-class challenges in the field of plastic processing:Solid-state mechanochemical processing—Based on the principles of polymer mechanochemistry,a novel solid-state shear milling(S3M)system with a unique three-dimensional shear structure was invented,enabling room-temperature ultrafine grinding of polymers,uniform nanofiller dispersion,and partial de-crosslinking of waste cross-linked plastics.In addition,a series of novel technologies for the solid-state mechanochemical prepara-tion and processing of polymeric materials was established and successfully applied in engineering.1)More than 20 types of polymer-based mi-cro/nano functional composites were prepared on a large scale,including PA11/BaTiO3(piezoelectric voltage constant 8 times higher than neat PA11),PA12/CNTs,and POM/MoS2.2)High-quality recycling of blended and cross-linked waste plastics was achieved.Representative examples included the high-value utilization of aluminum-plastic packaging,cross-linked polyethylene(XLPE)cables,and decommissioned wind turbine blades,which were successfully reprocessed into high-performance recycled products such as polyethylene geomembranes and corrugated pipes.3)The large-scale,high-value solid-state utilization of natural biomass materials,such as shells and cellulose,was achieved,providing an impor-tant pathway for addressing resource scarcity.3D printing of polymer materials—A series of polymer-based micro/nano functional composites suitable for selective laser sintering(SLS)and fused deposition modeling(FDM)was successfully prepared.A liquid-assisted spheroidization technique and a plasma-assisted solid-state mechanochemical spheroidization method were developed for SLS powders.Numerous polymer com-ponents with complex geometries and functional characteristics,such as piezoelectric devices,flexible sensors,and bone tissue engineering scaf-folds,were successfully fabricated by optimizing the 3D printing process.Micro-injection molding of polymer materials‒The Sichuan University-University of Bradford International Polymer Micro-processing Center was established and equipped with a range of advanced micro-processing equipment for polymeric materials.High-performance,multifunctional polymer-based micro/nano composites suitable for micro-processing were prepared on a large scale using methods such as organic/inorganic hybridization,solid-state shear milling,melt blending,and nanocomposite com-pounding.A series of advanced molds with replaceable cores,vacuum systems,and dual-temperature control systems was designed.Micro-gears(as small as 0.1 modulus,2.2 mg),micro-bone screws,and high-performance PVDF-based piezoelectric micro-sensors were produced,achieving a sensitivity of 85 mV/kPa.Rotation extrusion of plastic pipes—The team created axially deviated reinforced structures within the pipes by intro-ducing a rotating flow field during extrusion.This approach increased the hoop strength and crack resistance by more than 70%,producing PE100 pipes with the highest-pressure rating globally(14.9 MPa at 25℃and 6.6 MPa at 80℃).A novel rotation extrusion rheometer capable of nine different flow modes and online monitoring of temperature,pressure,and flow rate was also invented.In addition,rotation-extruded polypropyl-ene medical microcatheters and PE/carbon fiber conductive microtubes were prepared.Advanced foaming of plastics—Innovative equipment was developed,including a high-temperature twin-screw extruder capable of operating up to 450℃for supercritical CO2 foaming and a microwave selective heating system for bead fusion.Polyimide bead foams with a uniform cellular structure and a compressive strength of 4.14 MPa were produced using co-foaming agents(scCO2 and ethanol).Microwave-assisted fusion of carbon nanotube-coated PET beads enabled the production of lightweight,high-strength foams.Conductive PEI/CNT bead foams achieved an electrical conductivity of 20.7 S/m and excellent electromag-netic shielding performance.Thermoplastic processing of poly(vinyl alcohol)(PVA)—The team established a thermoplastic processing window above 120℃,solving the long-standing problem of PVA thermal degradation near its melting point by disrupting the hydrogen-bond network us-ing molecular complex agents.High-strength PVA fibers with a tensile strength of 1.9 GPa and a modulus of 39.5 GPa were produced through melt spinning.Blown PVA films and biaxially stretched films achieved tensile strengths of 140.6/146.4 MPa(MD/TD)and a puncture strength of 357.9 N/mm.PVA pipes exhibited a gasoline permeability as low as 0.97 g·mm/(m2·d).Self-lubricating PVA microcatheters with antimicrobial properties and PVA foams for cold-chain applications with a latent heat of 309.6 J/g were also developed.A supramolecular composite method was utilized to synthesize modified melamine cyanurate,reducing water consumption by 80%and reaction time by 75%,while enabling industrial-scale production(10 000 t/a).Reactive extrusion was employed to synthesize high-viscosity flame retardants in situ within the polymer matrix.An interfacial flame-retardancy strategy was proposed to concentrate low-content flame retardants at the glass fiber/polymer interface.This strategy reduced the horizontal burning rate of glass fiber-reinforced nylon 6 by 52%and achieved a UL94 V‒0 rating while maintaining the mechanical properties. Conclusions and Prospects Several advanced manufacturing and processing technologies have been successfully industrialized,and commercial production lines have been established.This has enabled the fabrication of high-performance,multifunctional,complex,miniaturized,and light-weight components,as well as high-value recycled plastic products that cannot be produced using conventional processing methods.These innovations have been widely applied in fields such as new energy vehicles,electronics,and construction,delivering substantial economic and social benefits.