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Carbon fiber reinforced (CFR) laminates have been manufactured by an innovative out-of-autoclave (OOA) process thanks to the use of smart materials. In this study, for the first time, a shape memory polymer (SMP) foam has been used into a pressure dome to apply the consolidation pressure to the laminate. Heat for resin curing was supplied by a thermal blanket between the laminate and the SMP foam. In order to test the OOA molding process, 24-ply CFR laminates were manufactured and tested. For comparison and reference, CFR laminates were also molded by traditional vacuum bagging and autoclave curing. Samples for bending tests were extracted from OOA and autoclave molded plates. Results show that the SMP-OOA process is able to provide optimal laminate consolidation, despite of the low applied pressure (about 1 bar). A comparable density and ply thickness was measured on samples by the innovative and the conventional molding process, whereas a higher bending strength (+5%) was found on OOA samples. A higher dispersion was also observed for the properties of SMP-OOA molded laminates in comparison with autoclave, probably due to the prototyping nature of the molding technique in comparison with the well-known autoclave practice. Nevertheless, the final quality of the molded laminates is very high, and the SMP-OOA process is a very promising candidate as a technology to repair CFR structures. [ABSTRACT FROM AUTHOR]

A new way for recycling polyurethane (PU) foams is shown by scrap pulverization and subsequent compression molding of resulting particles. The compression molding stage is also called 'direct molding' to highlight the absence of any linking agent or virgin material. Large disks, 190 mm in diameter, were molded by recycling foam scraps from motorcycle seats. Aluminum alloy molds and a hot parallel press plate press were used: the molding temperature was fixed to 180°C, the molding pressure to 4.2 MPa, and the molding time to 15 min, whereas the weight of the particles to mold was changed so as to obtain disks with different thickness. The final density of molded product was close to 1 g/cm3, resulting in a compacting factor of 14 in comparison with the initial PU foam. Indentation tests and tensile tests showed that final products exhibit good mechanical performances. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Foams of polycaprolactone (PCL) and microbial polyester (poly-hydroxybutyrate-hydroxyvalerate, PHBV with 10% mol PHV) were produced by particulate leaching in an urea preform and subsequent preform dissolution in distilled water. Films were also cast to compare mechanical and shape memory performances. SEM observations of foam sections showed that a homogenous microstructure was obtained with good replication of urea particles. Cylindrical PHBV samples (porosity about 90%) were used for shape memory tests in compression mode and a good behavior was observed. After training, 100% shape recovery can be achieved if a maximum 30% compression is applied. [ABSTRACT FROM AUTHOR]