Ravindra V Gadhave, Vineeth S K, Pritam V Dhawale, Pradeep T Gadekar
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引用次数: 17
Abstract
The work presented here focusses on developing adhesive by blending tannin and polyvinyl alcohol (PVA) in water. To furthermore enhance the properties crosslinking is carried by using boric acid at varying concentrations. Presence of free hydroxyl groups in PVA and tannin acts as a site for crosslinking reaction. The empty p orbital of trivalent boron atom attracts nucleophilic hydroxyl groups of PVA and tannin, hence are expected to form crosslinks. The interaction of boric acid with the blend was confirmed by FTIR spectra studies. The acidic pH favoured the reaction and its effects were observed by increase in viscosity and glass transition temperature (Tg). Films cased with the crosslinked blend demonstrated less hydrophilic behaviour from water contact angle test also increment in pencil hardness value and stress-bearing capacity. Adhesive performance properties like wet tack and time-dependent tensile lap shear strength on softwood and hardwood specimens were evaluated. The crosslinking-enhanced cohesion by reducing the free volumes between the chains and due to this, enhancement in tensile strength on bonded wood substrates was observed. Overall, it was found that the adhesive prepared by crosslinking PVA/tannin blend with boric acid is suitable for wood adhesive application.
期刊介绍:
Designed Monomers and Polymers ( DMP) publishes prompt peer-reviewed papers and short topical reviews on all areas of macromolecular design and applications. Emphasis is placed on the preparations of new monomers, including characterization and applications. Experiments should be presented in sufficient detail (including specific observations, precautionary notes, use of new materials, techniques, and their possible problems) that they could be reproduced by any researcher wishing to repeat the work.
The journal also includes macromolecular design of polymeric materials (such as polymeric biomaterials, biomedical polymers, etc.) with medical applications.
DMP provides an interface between organic and polymer chemistries and aims to bridge the gap between monomer synthesis and the design of new polymers. Submssions are invited in the areas including, but not limited to:
-macromolecular science, initiators, macroinitiators for macromolecular design
-kinetics, mechanism and modelling aspects of polymerization
-new methods of synthesis of known monomers
-new monomers (must show evidence for polymerization, e.g. polycondensation, sequential combination, oxidative coupling, radiation, plasma polymerization)
-functional prepolymers of various architectures such as hyperbranched polymers, telechelic polymers, macromonomers, or dendrimers
-new polymeric materials with biomedical applications