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Polymer and textiles have a vast number of advantages and attractiveness as a material. However, despite these advantageous, polymers have limitations. In general, special surface properties with regard to chemical composition, hydrophilicity, roughness, crystallinity, conductivity, lubricity, and cross-linking density are required for successful application of polymers in such wide fields as adhesion, membrane filtration, coatings, friction and wear, composites, microelectronic devices, thin-film technology and biomaterials, and so on. Unfortunately, polymers very often do not possess the surface properties needed for these applications. In fact, polymeric fibers that are mechanically strong, chemically stable, and easy to process usually will have inert surfaces both chemically and biologically. Vice versa, those polymers having active surfaces usually do not possess excellent mechanical properties which are critical for their successful application. Due to this dilemma, surface modification of the polymeric fibers without changing the bulk properties has been a classical research topic for many years, and is still extensive studies as new applications of polymeric materials emerge, especially in the fields of biotechnology, bioengineering, and most recently in nanotechnology. Modification is used to designate a deliberate change in composition or structure leading to an improvement in different type of fiber properties. The challenge is, however, that there does not exist an ideal modification that eliminates all the negative properties and preserves all the positive properties of the fibers. This is why there are a great number of different single-purpose modifications. [1]

The focus of this paper is to evaluate the mechanical and dynamic mechanical properties of woven jute fabric-reinforced green epoxy composites as a function of modification of jute fibers by enzyme, CO2 pulsed infrared laser and ozone treatments. The treated jute fibers were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. Composites were prepared by the hand layup method and compression molding technique and the resin curing process was optimized with the help of differential scanning calorimetry. The treatments resulted in the enhancement of flexural and impact properties. Statistical analysis of mechanical properties of composites, done by one-way analysis of variance, showed significant differences between the results obtained. Dynamic mechanical analysis (DMA) results revealed that treated composites have a higher storage modulus over the range of temperature. A positive shift of loss modulus and tangent delta peaks of treated composites to higher temperature was observed. The reduction in the tangent delta peak height of treated composites was also observed due to improvement in fiber/matrix interfacial adhesion. The degree of interfacial adhesion between the jute fiber and green epoxy was anticipated using the adhesion factor obtained through DMA data. Complex modulus variations and phase behavior of composites was studied by Cole–Cole analysis.

Cotton-titania nanocomposites with multifunctional properties were synthesized through ultrasonic acoustic method (UAM). Ultrasonic irradiations were used as a potential tool to develop cotton-titania (CT) nanocomposites at low temperature in the presence of titanium tetrachloride and isopropanol. The synthesized samples were characterized by XRD, SEM, EDX and ICP-OES methods. Functional properties i.e. Ultraviolet protection factor (UPF), self-cleaning, washing durability, antimicrobial and tensile strength of the CT nanocomposites were evaluated by different methods. Central composite design and response surface methodology were employed to evaluate the effects of selected variables on responses. The results confirm the simultaneous formation and incorporation of anatase TiO with average crystallite size of 4nm on cotton fabric with excellent photocatalytic properties. The sustained self-cleaning efficiency of CT nanocomposites even after 30 home launderings indicates their excellent washing durability. Significant effects were obtained during statistical analysis for selected variables on the formation and incorporation of TiO nanoparticles (NPs) on cotton and photocatalytic properties of the CT nanocomposites.

The growing concerns over desertification have spurred research into technologies aimed at acquiring water from non-traditional sources such as dew, fog, and water vapor. Some of the most promising developments have focused on improving designs to collect water from fog. However, the absence of a shared framework to predict, measure and compare the water collection efficiencies of new prototypes is becoming a major obstacle to progress in the field. We address this problem by providing a general theory to design efficient fog collectors as well as a concrete experimental protocol to furnish our theory with all the necessary parameters to quantify the effective water collection efficiency. We show in particular that multi-layer collectors are required for high fog collection efficiency and that all efficient designs are found within a narrow range of mesh porosity. We support our conclusions with measurements on simple multi-layer harp collectors.

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