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Using various micron-sized fillers with cylindirical, plate-like and spherical geometries in PU rigid foams enhances their closed-cellular morphology, mechanical properties, thermal insulation and stability, and flame retardant behavior. For cylindrical micron-sized fillers, synthetic and bio-based fibers can be given as the mostly used filler examples in PU rigid microcomposite foams (PURMCFs). Among plate-like micron-sized fillers, talc and expandable graphite can be given as the most popular additives that have been used in the fabrication of PURMCFs. For spherical micron-sized fillers, silica, calcium carbonate aluminum powder, glass powder, microspheres and carbon black can be given as examples that have been used as fillers in PURMCFs. This chapter systematically reviews important PURMCF works in detail by highlighting subtopics such as morphology, mechanical, thermal and thermomechanical properties, thermal degradation and flammability and recycling and recovery behavior. In addition, potential applications of PURMCFs containing various micron-sized fillers are discussed, and the main problems that are still not resolved and the future work about this important topic are addressed.

The aim of study was to compare properties of pure and recycled polyethylene blends with different filler content. Talc was compounded with two types of recyclable polyethylene: rLDPE and rLLDPE using a twin-screw extruder. The composites were blown moulded and the effect of the filler content on the end-use properties of blown films were investigated. Selected properties such as: mechanical, thermal and structure of composites were compared to virgin and recycled LDPE films. The effect of talc on crystallization and mechanical properties composites based on the recycled polymers as nucleating agent or/and inorganic filler were studied. It was shown that 30 wt. % amount of talc addition improved crystallization of 70L/30LL/30T. The degree of crystallinity improvement for the tensile strength, which were corresponding to crystallization analysis, so talc can play a role of heterogenous nucleation agent on PE and can be an effective filler to modify the PE matrix. The produced film is characterized by very good usable properties and satin-paper grip. The recycled composites can be used as a packaging material to group packs for ease of handling or tertiary packaging for ease of transport.

In Argentina, asbestos is associated with meta-mafic or meta-ultramafic igneous rocks, mainly serpentinites (or steatized varieties) and amphibolites, and less commonly with dolomitic rocks (in metamorphic and metasomatic domains). Chrysotile, anthophyllite and tremolite-actinolite were identified as the main asbestiform minerals (in the range of respirable particles). Chrysotile occurs mainly in serpentinites or steatized rocks as well as in amphibolites and other host rocks nearby. It appears filling veins, as slip and cross-fiber, generally associated with fissures or shear zones. Amphibole asbestos, mainly from the tremolite–actinolite series and anthophyllite, commonly occurs together with a non-asbestiform counterpart within the same area and deposits. These minerals have been found in talc ores as well as in vermiculite-rich sectors, or filling fissures in meta-mafic and meta-ultramafic rocks. In this compilation, the results of case studies on mines from the provinces of Cordoba, Mendoza and San Juan (Argentina) are summarized, and new data from the western sector of the Pie de Palo Complex are included.

Carcinomatous pleurisy is often a manifestation of malignant disease and an indicator of the terminal stage of disease. Breast carcinoma is one of the most common neoplasms and causes approximately one-third of all malignant pleural effusions (MPE). The ideal treatment is to remove the fluid and to prevent its re-accumulation. Various methods such as thoracentesis, chest tube drainage, permanent catheter placement, talc or other adhesive molecule use, and video-assisted thoracoscopic surgery (VATS) have been used to create pleural symphysis. Repeated thoracentesis controls less than 15 % of the effusions. A tunneled indwelling pleural catheter (TIPC) may improve symptoms for patients with MPE and does not appear to be associated with major complications; additionally, this method does not require hospitalization. TIPC also prevents the pain and complications that are associated with chemical agents. Pleurodesis with VATS has a very high efficacy in terms of effusion control if preoperative indications (complete pulmonary expansion) are respected. The advantage of pleurodesis with VATS is the possibility of conducting the procedure in direct view and achieving uniform talc distribution, even in the most inaccessible areas. Bedside talc pleurodesis has a high success rate when thoracoscopy is unavailable.

International audience; In automotive industry, polypropylene based composites are generally used in the manufacturing of car bumpers. In such a case, a detailed study of high strain rate and temperature sensitivities of polypropylene based composites is essential since the bumpers undergo compressive impact loading in a wide range of temperatures. The considered fillers consisted of ethylene octane copolymer and talc. The investigated filler content was 0, 10. and 20 wt. The dynamic behavior was investigated by using split Hopkinson pressure bars, at different strain rates and temperatures. We found that neat polypropylene and polypropylene talc composites were brittle at low temperatures. The addition of ethylene octane copolymer inclusions improved the impact resistance of materials. The dynamic properties are correlated with the morphological investigations of the studied composites by means of the optical microscopy. Finally, we also identify the effect of soft and rigid fillers in the quasi static to dynamic transition.

Soapstone is considered to be a low metamorphic, carbonated ultramafic rock containing talc, magnesite, dolomite, chlorite and iron oxides; however in a broader sense of use including also non-carbonated compositions. Talc-magnesite soapstones are the mostly utilized in a furnace use, because they have well-known heat resistance properties. In the field talc-magnesite appears to be generated over serpentine, when a magnesium-rich ultramafic rock has been reacted with carbon dioxide-containing metamorphic fluids at greenschist to lower amphibolite facies conditions. In principle, the soapstone occurs in a wide pressure temperature range P = 0.5–10 kbar, T = 200–600 °C even with fluid of low CO2 ratios, though unaltered serpentinites are found to be as common in the same prospect areas. The object of this study is to define regional metamorphic carbonate-fluid phase equilibria of diverse ultramafic whole-rock compositions locating in East Finland and how to use it in the practical exploration work of magnesite soapstone formations. Talc-carbonate assemblage showing isochemical P-T and binary T-X equilibrium phase diagrams, i.e. pseudosectios are compiled by Theriak-Domino thermodynamic modelling program. Software is designed to calculate and plot the most correct stable assemblages for a given multi-component bulk chemical composition and case by case user-experimented H2O-CO2 fluid mixtures at prevailing pressure temperature condition. Unassisted calculating, general thermodynamic data sets utilizing program is based on Gibbs free energy minimization.