Adhesion of grafted polypropylene plates with enzymatically modified chitosan solutions and analysis of failed surfaces by X‐ray photoelectron spectroscopy

Abstract

In this study, hydrophilic monomers were photografted onto the PP plates at different monomer concentrations and temperatures, and grafted PP plates were bonded with enzymatically modified chitosan solutions. Their adhesive strength properties were discussed in relation to the grafting conditions and hydrophilic properties such as wettability and water-absorptivity. In addition, the location of failure was investigated by X-ray photoelectron spectroscopy analysis of failed surfaces. Wettability of the grafted PP plates except for the PP grafted with acrylic acid (PP-g-PAA) plates remained constant above the grafted amounts at which the PP surfaces were fully covered with grafted polymer chains. On the other hand, wettability of the PP-g-PAA plates passed through the maximum value and then gradually decreased with the grafted amount probably because of the aggregation of grafted PAA chains. Waterabsorptivity of the grafted layers formed at lower monomer concentrations or temperatures sharply increased at lower grafted amounts. The adhesive strength increased with an increase in the grafted amount and substrate breaking was observed for PP-g-PAA plates because enzymatically modified chitosan solutions were successfully penetrated in the grafted layers and quinone derivatives reacted with carboxy groups of grafted PAA chains. Failure occurred in the layers composed of grafted PAA chains and components containing in enzymatically modified chitosan solutions and the location was shifted to the inside of grafted layer, as the grafted amount increased.

Development of Water-Resistant Autohesive Strength of Polyethylene Plates with Photografting of Alkyl (Meth)Acrylates

“…After grafting, the PE plates were washed with excess acetone several times to remove the homopolymers, and then dried under a reduced pressure. The grafted amount was calculated in µmol/cm 2 from the weight increase in the PE plates using Equation (1) [24,[26][27][28].…”

Improvement of Adhesive Strength of Poly(tetrafluoroethylene) Plates through Oxygen Plasma Treatment and Subsequent Photografting of Methacrylic Acid

“…15.6 cm 2 ). Although the grafted amount was calculated in wt% or mmol/g in other articles [39][40][41][42], the unit of µmol/cm 2 was used in this study because of the fact that the grafted amount in µmol/cm 2 is independent of the thickness, density, or weight of the PTFE plate [20][21][22][25][26][27]].…”

“…These characteristics can be controlled by the temperature and initial monomer concentration on the photografting [21,22,25]. As a result, the substrate breaking was observed for adhesion or autohesion of the grafted LDPE, HDPE, and PP plates at a high grafted amount [20][21][22][25][26][27]. This means that the strengths of adhesion and autohesion exceed the ultimate strength of each polymer substrate.…”

Preparation of polypropylene chelating fibers by quenching pretreatment and suspension grafting and their Pb2+ adsorption ability

“…The pollution problems associated with organic solvents and highly expensive post process of the finial product limit the application of solution grafting in industry [12,13,16]. The irradiation grafting employs high-energy particles to initiate grafting polymerization and requires specialized equipment, which is difficult to industrialize [4,7,[17][18][19][20][21]. The solid-phase grafting employs the surface of PP particles for grafting monomers [13], but suffers from the problems of particle adherence and poor heat and mass transfer.…”

“…However, the weak molecular polarity and poor hydrophilicity of PP cause its fibers to poorly adsorb polar molecules and metal ions in water [5][6][7][8][9][10].…”