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Polymer adhesion promoters were formulated to improve the adhesion strength of lead frame/epoxy composites. The poly(itaconic acid-co-acrylamide) CIAcAAM) was synthesized via free radical polymerization to improve the interfacial adhesion between Ni and Cu lead frames and epoxy composites. IAcAAM was synthesized by setting itaconic acid (IA) and acrylamide (AAM) at molar ratios of 7:3, 5:5. and 3:7. The interfacial adhesion mechanism was investigated by introducing IAcAAM with three different comonomer molar ratios. The adhesion strength between EMC and Cu and Ni substrates to which each IAcAAM was applied was measured using a universal testing machine, and the effect of IAcAAM with various LA:AAM molar ratios on the surface energy of EMC was closely studied. As a result, the adhesion properties of Ni lead frame/epoxy composite and Cu lead frame/epoxy composite were improved as small amounts of all IAcAAM samples were added to the epoxy mixture. We confirmed that IAcAAM with an appropriate molar ratio can be used in the EMC process and has the potential to increase the adhesion of epoxy composites and metal lead frames. Highlights * A polymeric adhesive promoter was synthesized to enhance the adhesion strength of lead frame/epoxy composites. * Poly(itaconic acid-co-acrvlamide) (IAcAAM) was copolymeriz,ed from itaconic acid and acrylamide for this purpose. * The adhesion strength of lead frame/epoxy composites was compared for different IAcAAM monomer contents and with a commercial adhesive promoter. * IAcAAM showed superior adhesion strength in the Ni lead frame/epoxy composite material. * The highest adhesion strength was achieved at a monomer composition of 5:5. KEYWORDS adhesion promoter, adhesive strength, epoxy composite, epoxy molding compound, lead frame, 1 | INTRODUCTION An epoxy molding compound (EMC) is a composite material composed ol' ingredients such as silica, epoxy resin, phenolic resin, carbon black, and flame retardants. This compound is [...]

The biological degumming of silk fibers was studied using alkaline proteases such as Savinase and Alcalase, comparing with conventional alkaline treatments. Degumming efficiency was evaluated by measuring the residual silk sericin in terms of weight loss and surface staining with reactive dye. The water absorbency and tensile strength were measured to characterize surface and physical properties, and the results are presented. The dosage was the decisive factor in enzymatic degumming process. Finally, the morphology of silk fibers was researched by scanning electronic microscopy, and the regular removal of sericin and less damage to fibroin were detected in enzymatically treated fibers. [ABSTRACT FROM AUTHOR]

A facile method to prepare hybrid cellulose acetate nanofibers containing TiO2 (TiO2-CA nanofibers) by emulsion electrospinning technique was developed for the denitrification and filtration of particulate matters (PMs). This work found that hybrid TiO2-CA nanofibers mainly contain the anatase form of TiO2, contributing to the photodecomposition of NO gas under UV irradiation. The TiO2-CA nanofibers also showed an excellent filtration efficiency of 99.5% for PM0.5 and a photocatalytic efficiency of 78.6% for NO removal. Furthermore, the results implied that the morphology of the TiO2-CA nanofibers, such as micro-wrinkles and protrusions, increased the surface hydrophobicity up to 140°, with the increased addition of TiO2 nanoparticles. The proposed TiO2-CA nanofibers, as a result, would be promising materials for highly efficient and sustainable air filters for industrial and home appliance systems. [ABSTRACT FROM AUTHOR]