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Poly(ethersulfone)s (PES) with active carboxylic acid groups, as branch in the main chain, were prepared in order to obtain membranes, by solution polymerization via nucleophilic displacement polycondensation reaction between various amounts of 4,4'-bis (4-hydroxyphenyl) valeric acid (DPA) and 4,4'-sulfonyldiphenol (DHDPS) with 4,4'- dichlorodiphenyl sulfone (DCDPS). The novel synthetic route developed here let to obtain structures with tailored thermal properties, which were investigated by the means of dynamic mechanical analysis (DMA). In addition to that, preliminary testing have showed that these polymers can be used in membranes for removing heavy metals from water. [ABSTRACT FROM AUTHOR]

A typical steel rebar can be bend using traditional bending machines without much of a problem. Glass Fiber Reinforced Polymer (GFRP) rebar possesses very less tensile strength, being thermoset in nature, will break easily and so cannot be bend on site. The present work addressed the problem of producing GPR rebar with the same materials used in standard pultrusion but, by modifying the process, with the possibility to bend them. The results showed bending is possible when accurate cure control is made. [ABSTRACT FROM AUTHOR]

This manuscript represents an experimental investigation about the thermal properties of polymeric Polyetherimide (PEI) / Polyethyleneterephthalate-glycol (PEG) blends, with the aim to improve the processability of pristine PEI without an excessive decrease of its properties, thus obtaining a suitable material to feed machines for rapid prototyping, in particular for the fusion deposition modelling (FDM) production technique. Mixtures with 5 and 10% of PETG were obtained applying the melt blending technique using a batch mixer. The materials obtained from the latter were subjected to a thermomechanical process in order to obtain pellets, used as feed for an injection-moulding machine, thus suitable to be employed for the various characterizations. The blends were characterized through thermal (TGA and DSC) and morphological (SEM) analysis. [ABSTRACT FROM AUTHOR]

Automotive composite applications are increasingly growing due to demand for lightweight structures to comply to the requirements for fuel reduction. HP-RTM is gaining relevance as one of the preferred production technologies for high volume applications. The BMW i3 life module being a notable example of HP-RTM application. The key aspects of HP-RTM are the short injection times (i.e. less than 1min) and the fast curing of the thermoset resins (i.e. less than 10min). The choice of using thermosets poses relevant issues for their limited recycling options. The standard recycling solution is the incineration but, this solution poses some concerns in terms of global environmental impact. Novel solutions are presented in this work based on the use of recyclable epoxy systems. In our work the results of experimentation carried out by our group with cleavable ammines by Connora Technologies and bioepoxy resins by Entropy Resins will be discussed. The multiple uses of recycled matrices obtained treating the recyclable epoxy resins are discussed in the framework of a "cradle" to "crave" approach. Finally, Life Cycle Assessment (LCA) is used to evaluate the environmental benefits of the proposed approach. [ABSTRACT FROM AUTHOR]

Liquid Wood (a mixture of cellulose, hemp, fax and lignin) was used to prepare, by mechanical mixing followed by thermal extrusion, blends of various Polypropylene (PP)/Liquid Wood ratios. To verify if and how much the composition of the obtained composites affects their thermal properties Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) experiments were carried out. [ABSTRACT FROM AUTHOR]

The present paper is focused on the development of a novel technique to obtain multifunctional fiber reinforced composites. The technique is based on the use of thermoplastic veils composed of nano and micro thermoplastic fibers which preferentially dissolve upon curing in the epoxy matrix. The technique allows to control the phase morphology in the inter- and intra-laminar region of the laminates. Moreover, the selective dissolution of the fibers allow to achieve tailored dispersion of different types of nanofillers in the composites to obtain a functional graded material. [ABSTRACT FROM AUTHOR]

The thermal and mechanical properties of a monochlorophenyl, hepta isobutyl Polyhedral Oligomeric Silsesquioxane/Polystyrene (ph,hib-POSS/PS) composite were studied and compared with those of pristine polymer. ph,hib-POSS/PS system was prepared by solubilization and precipitation of Polystyrene (PS) in the presence of POSS. Scanning Electron Microscopy (SEM) was performed to check the distribution of the filler in the polymer matrix. Dynamic Mechanical Analysis (DMA) was carried out to measure viscoelastic properties of solid samples. Degradations were carried out into a thermobalance and the obtained thermogravimetric (TG) and differential thermogravimetric (DTG) curves were discussed and interpreted. [ABSTRACT FROM AUTHOR]

Some novel ABA block copolymers, synthesized with three different molecular weights, where the block A is a PPO while the block B is a random copoly(aryl ether sulfone), were studied by TGA and DTA techniques, in both flowing nitrogen and static air atmosphere, in order to draw useful information about their resistance to thermal degradation. The results obtained for the various compounds investigated were discussed and compared with each other and a thermal stability classifications in the studied environments were made. [ABSTRACT FROM AUTHOR]