Elastomer foams with customized multimodal cellular structures have great application requirements in advanced fields, but a simple and practical way to realize it needs be further studied. Herein, strategy of presetting cells into elastomers before supercritical CO2 foaming was introduced customize the structures. Typically, taking olefin block copolymers (OBC, thermoplastic elastomer crystalline hard segments rubbery soft segments) as an example, bimodal, sandwich, gradient were...

In this study, the crosslinked ethylene–propylene–diene monomer (EPDM) foams were prepared by batch foaming using compressed CO2 as blowing agent. The various crosslinking structures, i.e., local primary structure, micro-crosslinking and full generated adjusting loading of models established to illustrate fundamental influences structures on evolution cell morphology. EPDM-0.2B with 0.2 parts per hundred rubber (phr) agent had which improved foamability EPDM significantly. temperature window...

An efficient and green preparation strategy is critical in promoting the marketization of expanded polypropylene (EPP) products. In this work, supercritical CO2 extrusion foaming cooperating with wind-cooling granulator technology was creatively used to prepare (PP)/thermoplastic polyurethane (TPU) composite bead foams controllable cellular structures geometric shapes like capsule, sphericity, pie shaped. It found that addition TPU can help promote uniform structures. More importantly,...

Abstract Polylactic acid (PLA) is a bio‐based and biodegradable polymer. It challenging to prepare PLA bead foams at large scale in an efficient manner. Herein, beads of modified are foamed by one‐step anhydrous supercritical CO 2 extrusion. This dramatically shortens the production time, prevents from pyrohydrolysis, avoids wastewater generation. The melt strength increased 0.8 16.7 cN using chain extender. morphologies microstructures analyzed. In case foam obtained extrusion foaming...

This paper provides a comprehensive review of the seismic design and renovation strategies for reinforced concrete (RC) structures in civil engineering. It begins with an introduction to importance design, considering potential threat earthquakes RC structures. then elaborates on current codes, principles, methods, including load calculations, structural system detailing requirements. Retrofit such as reinforcement fiber-reinforced polymers (FRP), steel sheaths, isolation techniques were...

The structural characteristics of the polymer composite foams play an important role in their properties. Herein, polypropylene/polylactic acid (PP/PLA) with controllable hollow radially gradient porous structures are designed and prepared by supercritical CO2-assisted foam extrusion coupled postdrawing auxiliary technology. above consist dense skin layer, hollow-core, closed-cell, open-cell. Under constant foaming temperature pressure, outer diameter as-prepared can be adjusted from about...

Lightweight polyolefin elastomer (POE) foams are of great interest in numerous fields. However, POE is difficult to foaming and obtaining the ideal cellular structures before cross-linking. Herein, low-molecular-weight trans-polyoctylene rubber (TOR) with lots double bonds low molecular weight was introduced into matrix improve their vulcanizing process. Then, a series lightweight POE/TOR composite adjustable outstanding performance were prepared by supercritical CO2 foaming. It worth noting...

Expanded polypropylene (EPP) foams have showed wide applications in our daily life, such as automotive and packaging. Usually, autoclave foaming combined with steam-chest molding is the main artwork to prepare high-precision EPP foam products. However, behavior of excessive pressure required for still need be further improved, which great significance energy saving cost saving, etc. Herein, this study finds that adding a certain amount polybutene-1 (PB-1) into PP can help reduce temperature...

scCO₂-aided IFR dispersion of PP/IFR composites and their improved flame retardancy.

Abstract Trans‐1,4‐polyisoprene/single wall carbon nanotubes nanocomposites (TPI/SWCNT) with thermo‐ and electro‐active shape memory performance were prepared via solution blending vulcanization. Herein, the mechanical, thermo‐mechanical, electric conductivity properties, properties of pure TPI TPI/SWCNT investigated. It was demonstrated that addition SWCNT into matrix can improve its crystallinity, crystallization temperature storage modulus characteristics, form a two‐crystal melting peak....

Abstract Compatibility of polycarbonate (PC) and polymethyl methacrylate (PMMA) alloys was improved by using a transesterification catalyst (SnCl 2 ·2H O). Modified PC/PMMA exhibit single T g , their initial island phase existing in the SEM were transformed into uniform surface. Besides, transmittance modified increased from original 40% to 85%. Moreover, PC foams with micro‐cellular nano‐cellular structures prepared solid‐state CO foaming presence catalyst. Distinctively, there are obvious...

Owing to the problems existing in traditional technologies for preparing commercial cellulose acetate (CA) cigarette filters, such as complex processing and chemical solution usage, novel lightweight polypropylene (PP) foams with similar geometries but different porous structures were designed successfully prepared filters potentially hazardous materials via supercritical CO2 (scCO2) extrusion foaming technology without use of any harmful reagents floating micro-nano fibers. Interestingly,...

Abstract Polycarbonate (PC) composites are often used in the production of high value‐added products, but it is necessary to improve its environment stress cracking condition presence pre‐strain and soluble solvents. In this work, effect weight reduction strengthening realized by introducing microstructures hollow glass microspheres (HGMs) into PC composites. It found that addition HGMs can reduce melt viscosity T g value composite materials, which will change foaming behavior PC/HGMs...

The new approach of applying scCO₂as a processing medium was proven effective in tuning the fracture behavior PP/POE blends.