Studying the effect of silica (SiO2) addition on the adhesive properties of polyvinyl alcohol

The work concerned with studying the effect of (SiO2) addition as afiller on the adhesive properties of (PVA). Samples were prepared assheets by using casting method. The mechanical properties showedthat increase in tensile strength from (34MPa) to (68MPa) when(SiO2) added to (PVA). The adhesive strength showed that jointproperties depend upon specific adhesive characteristic of material(PVA) and (SiO2\PVA)composites at different concentrations (1.5%,2.5%, 3.5%, 4.5wt%), the cohesive strength of the adhesive material,the joint design, and adherent type (Sponge Rubber(SR), Naturalleather (NL), Vulcanized Rubber(VR), and Cartoon). The resultsproved the tensile strength increased with (SiO2) ratio, so it can beused as the adhesive material. Shear strength showed an increasewith (SiO2) ratio of sponge rubber, and cartoon adherent, whereas itwas increased up to 2.5% for Natural Leather, and VulcanizedRubber then decreased; That suggested it is most suitable for spongerubber adhesive and cartoon than the other adherents.

Recent Trends in Mussel-Inspired Catechol-Containing Polymers (A Review)

Syntheses and applications of mussel-inspired polymeric materials have gained a foothold in research in recent years. Mussel-inspired chemistry coupled to Michael addition and Schiff’s base reactions was the key success for this intensive research. Unequivocally, The basic building brick of these materials is catechol-containing moiety, namely, 3,4-dihydroxyphenyl-L-alanine (L-DOPA or DOPA) and dopamine (DA). These catechol-based units within the chemical structure of the material ensure chiefly its adhesive characteristic to adherends of different natures. The newly-made catechol-bearing polymeric materials exhibit unique features, implying their importance in several uses and applications. Technology advent is being advantaged with these holdfast mussel protein-like materials. This review sheds light into the recent advances of such mussel-inspired materials for their adhesion capacity to several substrata of different natures, and for their applications mainly in antifouling coatings and nanoparticles technology.