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PVC is a versatile polymer used in a diversity of applications, function of its own, as well as its blending component’s properties. Since the early 1930s, when commercial production of PVC started, it became a universal polymer due to its high performance and low cost, combined with the broad range of items that can be obtained by multiple processing techniques and variable parameters. For enhanced performances, PVC can be mixed with (bio)plasticizers, thermoplastics, rubbers, polysaccharides, minerals, natural fillers or other types of additives in order to improve PVC blends compatibility. PVC is found in various applications, such as building, packaging, automotive, military and aeronautic industries, medicine, ships construction, life rafts, garden hoses, swimming rings, footballs, toys, different cards and so on. PVC is also used in the preparation of membranes (e.g., for water treatment), owing to its good mechanical strength, abrasion resistance, chemical stabilization, thermal properties, low cost and corrosion resistance. Different factors affect the properties of PVC composites, such as processing techniques and parameters, the origin of the filler, its particle size and its aspect ratio, as well as its concentration and the homogeneity of its distribution in the polymer matrix. PVC bionanocomposites can be also produced by using nanoelements resulted from different renewable resources, e.g., cellulose, starch, chitin, inducing also PVC’s biodegradability.

The epoxy composites were synthesized from epoxy resin ED-20, polyethylene polyamine as curing agent and copper nanopowder and boric acid as fillers. The copper nanopowder was produced by electrical explosion of wires. The thermal properties of the epoxy composites at the heating in the atmosphere of air and argon from ambient temperature to 900 °C were characterized using thermogravimetric analysis and differential scanning calorimetry. The results showed that copper nanopowders catalyzed thermal oxidative degradation of the epoxy composites. The effect of the addition of boric acid in the epoxy polymer filled with copper nanopowder on the thermal stability of the composite at the heating in air was studied. It was found that the boric acid addition inhibited the degradation process. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation.

The epoxy resins are widely used in nuclear and aerospace industries. The certain properties of epoxy resins as well as the resistance to radiation can be improved by the incorporation of different fillers. This study examines the effect of electron beam irradiation on the thermal and mechanical properties of the epoxy composites filled with aluminum nanoparticles at percentage of 0.35 wt%. The epoxy composites were exposed to the irradiation doses of 30, 100 and 300 kGy using electron beam generated by the linear electron accelerator ELU-4. The effects of the doses on thermal and mechanical properties of the aluminum based epoxy composites were investigated by the methods of thermal gravimetric analysis, tensile test, and dynamic mechanical analysis. The results revealed that the studied epoxy composites showed good radiation resistance. The thermal and mechanical properties of the aluminum based epoxy composites increased with increasing the irradiation dose up to 100 kGy and decreased with further increasing the dose.

The particles of natural zeolite in combination with boric acid were incorporated into the epoxy resin ED-20 in order to improve the thermal stability of epoxy polymer. Epoxy resin was cured using polyethylenepolyamine. Characterization of the epoxy composites was carried out by using Fourier transform infrared spectrometry, thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) under flow of air and argon. The thermal behavior of the zeolite/boric acid-based epoxy composites (total percentage 15 mass%) were compared with that of 15 mass% boric acid-based epoxy system and the neat epoxy resin. TG and DSC results revealed that the combination of 5 mass% zeolite and 10 mass% boric acid significantly increased the mid-point temperature and residue, and decreased the maximum decomposition rate of the epoxy composites at the heating.

Epoxy composites filled with boric acid and natural zeolite with different percentage (1, 5, and 10 wt%) were prepared. Hexamethylenediamine and polyethylenpolyamine were used as curing agents. The prepared samples and starting materials were examined using the methods of thermal analysis and scanning electron microscopy. The parameters of thermal decomposition in argon were analyzed. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation. The thermal characteristics of the studied composites depend on the filler content. The results showed that the incorporation of 10 wt% fillers both boric acid and natural zeolite significantly improved the thermal properties of the obtained composites. Copyright © 2016 John Wiley & Sons, Ltd.

Natural fibres have recently become attractive to scientific community as an alternative reinforcement for fibre reinforced polymer (FRP) composites. As compared to conventional fibres, such as glass and carbon FRPs have low cost, fairly good mechanical properties, ecofriendly and bio-degradability characteristics. In the present work, bio based nanocomposites were successfully developed using cellulose nano whisker as filler in natural rubber latex by water evaporation method. The cellulose nano whisker were prepared from “Moringa oleifera” (Drum Stick vegetable Fibre) by acid hydrolysis. The morphology of cellulose whiskers/NR nanocomposites was investigated by Scanning Electron Microscope. The presence of nano cellulose whiskers (CW) in the NR matrix was observed by using Fourier transfer-infra red (FTIR) spectroscopy. The tensile properties such as tensile strength, tensile modules and elongation at break were measured by Universal Testing Machine. Thermal degradation of the nanocomposites were also analyzed using thermal gravimetric analysis (TGA). The result of the study shows that CW in the nanocomposites prepared during this study are randomly oriented and distributed homogeneously throughout the matrix. The FTIR analysis provided clear evidence of the presence of nano CW in the NR matrix that can be observed by the absorption peaks at 1033 and 1057 cm−1 assigned to C–O stretching of cellulose and TGA analysis showed the thermal stability of the nanocomposites increased with increasing CW, tensile strength and modulus values were also increased with CW addition. Hence the present study shows that the cellulose nano whiskers from Moringa oleifera has improved the properties of natural rubber based composite and can be considered as a good natural reinforcing material for future applications.

Polymer blends have been intensively studied because of their theoretical and practical importance. A polymer blend/nanocomposite can be defined as a polymer-nanofiller system in which the inorganic filler is on a nanometric scale at least in one dimension and it can be a polymer/nanoparticle blend or a hybrid. Polymer blends are utilized in various applications based on their properties. The most wide-ranging definition of a hybrid is a material that includes two moieties blended on the molecular scale. Commonly the term hybrids is more often used if the inorganic units are formed in situ by the sol–gel process. Meanwhile, use of the word nanocomposites implies that materials consist of various phases with different compositions, and at least one constituent phase (for polymer/silica nanocomposites, that phase is generally silica) has one dimension less than 100 nm. Polymer blend nanocomposite systems can be prepared by various synthesis routes because of their ability to combine in different ways to introduce each phase. The characterization methods used in the analysis of the chemical structure, microstructure, and morphology as well as the physical properties of the nanocomposites are varied Polymer blend nanocomposites received significant attention because of the new and superior properties (eg, electrical, thermal, and mechanical) compared with conventional composites of these materials, and they may be synthesized using surprisingly simple and inexpensive techniques.

The epoxy composites filled with unmodified zeolite of 5 and 10 wt. % and modified natural zeolite of 10 wt. % were prepared. The modification of zeolite with nanofibers of aluminum oxyhydroxide was carried out. Aluminum oxyhydroxide nanofibers were produced at the heating and oxidation of aluminum powder with water. The tensile properties of all the samples were studied. The mechanical properties of modified zeolite based composite were significantly increased compared with that of unmodified zeolite based composite.

Crosslinked natural rubber (NR) nanocomposites were prepared using cellulose nanowhiskers (CNWs) that were extracted from bamboo pulp residue of newspaper production, as the reinforcing phase. The coagulated NR latex containing bamboo nanowhiskers (master batch) was compounded with solid NR and vulcanizing agents using a two-roll mill and subsequently cured to introduce crosslinks in the NR phase. No evidence of micro-scaled aggregates of cellulose nanowhiskers in NR matrix was observed in Scanning Electron Microscopy (SEM) images. The addition of CNWs had a positive impact on the tensile strength, E-modulus, storage modulus, tan delta peak position and thermal stability of the crosslinked NR. Theoretical modeling of the mechanical properties showed a lower performance than predicated and therefore further process optimization and/or compatibilization are required to reach the maximum potential of these nanocomposites.

The addition of small amounts (up to 9 wt%) of chitin microsized particles, originating from shellfish waste, to carboxylated styrene-butadiene rubber (XSBR) matrix (as received and annealed to 100°C) has been studied. In particular, this study concentrated on their mechanical (creep investigation by nanoindentation and dynamical-mechanical analysis), thermal (differential scanning calorimetry and thermogravimetry) and swelling behaviour (toluene absorption) and was completed by morphological characterisation by scanning electron microscopy and atomic force microscopy. The results show that annealing has a limited effect on materials properties, effects which are further reduced by the addi- tion of growing amounts of crab chitin. It should be noted that the limited filler content used in the study does not substan- tially modify the linear creep behaviour of XSBR for sufficiently long loading times. The thermal stability of the system does also appear to be preserved even with the maximum chitin content added, while it serves sufficiently as an effective barrier against aromatic solvent absorption.

Received 9 May 2011; accepted 28 June 2011DOI 10.1002/app.35176Published online in Wiley Online Library (wileyonlinelibrary.com).ABSTRACT: This article investigates the transport behav-ior of three aromatic organic solvents, viz. benzene, toluene,and p-xylene in natural rubber nanocomposite membranescontaining cellulose nanofibres (CNFs) and cellulose nano-whiskers (CNWs) isolated from bamboo pulp. The solventmolecules act as molecular probes to study the diffusion,sorption, and permeation through the nanocomposites, andprovide information on the nanocomposite structure and ma-trix–filler interactions. Both the nanocelluloses were found todecrease the uptake of aromatic solvents in nanocompositemembranes, but the effect was more significant in the caseon nanofibers compared to nanowhiskers. Furthermore, theuptake decreased with increased penetrant size; being thehighest for benzene and the lowest for p-xylene. Transportparameters such as diffusion coefficient, sorption coefficient,and permeation coefficient have been calculated. Comparisonof the experimental values of equilibrium solvent uptakewith the predicted values indicated that both the nanocellu-loses have restricted the molecular mobility at the interphaseand thereby decreased the transport of solvents through thematerials; being more significant for nanofibers. The resultsshowed that both the used cellulosic nanomaterials act asfunctional additives capable of manipulating and tailoringthe transport of organic solvents through elastomeric mem-branes, even at concentrations as low as 2.5 wt %.

The epoxy polymers are characterized by low thermal stability and high flammability. Nanoparticles are considered to be effective fillers of polymer composites for improving their thermal and functional properties. In this work, the epoxy composites were prepared using epoxy resin ED-20, polyethylene polyamine as a hardener, aluminum nanopowder and boric acid fine powder as flame-retardant filler. The thermal characteristics of the obtained samples were studied using thermogravimetric analysis and differential scanning calorimetry. The mechanical characteristics of epoxy composites were also studied. It was found that an addition of all fillers enhances the thermal stability and mechanical characteristics of the epoxy composites. The best thermal stability showed the epoxy composite filled with boric acid. The highest flexural properties showed the epoxy composite based on the combination of boric acid and aluminum nanopowder.

The present chapter deals with a brief account on various topics in polyaniline-based blends, composites, and nanocomposites. This chapter discussed with different topics such as polyaniline structure–properties relationship; modification of polyaniline; polyaniline nano-/micromaterials–based blends and composites; polyaniline-based thermoplastic blends; polyaniline-based blends: natural rubber and synthetic rubber; polyaniline-based composites and nanocomposites; characterization of polyaniline-based blends, composites, and nanocomposites; polyaniline/natural polymer composites and nanocomposites; applications of polyaniline-based blends, composites, and nanocomposites; other applications of polyaniline-based blends, composites, and nanocomposites; and polyaniline–nanomaterial composites: structural, optical, and electrical properties.

This chapter deals with a brief account of thermal degradation of polymer-based blends, composites and nanocomposites. Different synthesising, preparation and characterisation methods of thermal degradation of polymer-based blends, composites and nanocomposites are discussed. Finally the applications, new challenges and opportunities for these thermal degradation of polymer-based blends, composites and nanocomposites are discussed.

The present chapter deals with a brief account on various types topics in flame retardant of polymer nanocomposites. This chapter discussed with different topics such as flame retardancy of polymer nanocomposite, recent developments in different techniques used for the flame retardancy, recent development of phosphorus flame retardants in thermoplastic blends and nanocomposites, non-halogen flame retardants in epoxy-based composites and nanocomposites, flame retardant/resistant based nanocomposites in textile, flame retardants in bitumens and nanocomposites, fire retardant for phase change material, flame retardant finishing for textiles, flame retardant of cellulosic materials and their composites.

The thermal properties of epoxy composites filled with boric acid fine powder at different percentage were studied. Epoxy composites were prepared using epoxy resin ED-20, boric acid as flame-retardant filler, hexamethylenediamine as a curing agent. The prepared samples and starting materials were examined using methods of thermal analysis, scanning electron microscopy and infrared spectroscopy. It was found that the incorporation of boric acid fine powder enhances the thermal stability of epoxy composites.

Polyoxymethylene (POM) is a semicrystalline polymeric material belonging to engineering thermoplastics because of its low friction and wear characteristics and its excellent balance of mechanical properties and chemical resistance to most solvents, chemicals and fuels at room temperature. Hence, such polymers are used to serve as an alternative to metals. As formaldehyde was initially the raw material used in the manufacturing of commercial POM it is also referred to as polyformal or polyacetal. Among the polymers obtained from the polymerization of aldehydes, POM is the only one that could reach commercial signifi cance. Polyoxymethylene resins have traditionally covered homopolymers (POM-H) and copolymers (POM-C), and more recently terand block-copolymers have been developed. Today, most of the POM resins manufactured worldwide are used in the production of automotive parts followed by electrical and electronic parts, and industrial parts. Hence, at present most of the POM is manufactured and consumed in Asia. However, besides Asia, manufacturing sites with high production capacities are also located in Germany and the USA.

The field of elastomers, their composites and nanocomposites has gained a lot of interest in recent years. These composite materials have great significance both from the fundamental and application point of view. Since this field is growing at a faster rate, it is always necessary to address the structure, properties and applicability of such materials. The present chapter gives a brief account on various elastomer systems, their composites and nanocomposites. Various topics such as elastomer based macrocomposites, nanocomposites, interphase modification, compatiblisation of rubber based nanocomposites, fully green elastomer nanocomposites, elastomeric micro and nanocomposites for tyre applications, elastomer based bionanocomposites, bio-medical applications of elastomeric composites and nanocomposites have been very briefly discussed. Finally the applications, new challenges and opportunities of these composites and nanocomposites are also discussed.

The present chapter deals with a brief account on various types of natural polymers such as cellulose, chitin, starch, soy protein, casein, hemicelluloses, alginates, polylactic acid and polyhydroxyalkanoates etc. Blends, composites and nanocomposites based on these polymers have been very briefly discussed. Finally the applications, new challenges and opportunities of these biomaterials are also discussed.

The chapter presents a brief account of various topics in starch-based blends, composites and nanocomposites, including structure–property relationships, preparation and characterization of starch nanocrystals, natural fibre-reinforced thermoplastic starch composites, applications of starch nanocrystal-based blends, composites and nanocomposites, chemically modified thermoplastic starches, outstanding features of starch-based hydrogel nanocomposites, fracture and failure of starch-based composites, application of starch-based nanocomposites in the food industry and effects of additives on the properties of starch.

Validerad; 2012; Bibliografisk uppgift: Nanocomposites were prepared using two bioresources, viz., cellulose nanofibers (CNFs) extracted from bamboo paper-pulp waste as the reinforcing phase and natural rubber (NR) as the matrix phase. CNFs with diameters up to 50 nm were isolated from bamboo pulp waste, and nanocomposites with 5 and 10% CNFs were obtained via two-roll mill mixing of solid natural rubber with a master batch containing 20 wt% CNFs. The NR phase was cross-linked using sulphur vulcanization. The morphology studies showed that the dispersion of CNF in NR matrix was not optimal, and some aggregates were visible on the fracture surface. The tensile strength and modulus at 50% elongation increased for the nanocomposites with the addition of CNFs, accompanied by a moderate decrease in elongation at break. The storage modulus of the natural rubber significantly increased above its glass-rubber transition temperature upon nanofiber addition. The addition of CNFs also had a synergistic impact on the thermal stability of natural rubber. The susceptibility to organic solvents decreased significantly for the nanocomposites compared to crosslinked NR, which indicated restriction of polymer chain mobility in the vicinity of the nanosized CNFs in the NR matrix.; 20120807 (ysko)