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In this study, new synthesis strategies for poly (vinyl alcohol) (PVA) functionalized with azidation (Az) and alkynation (Alk) were carried out for surface functionality modification. These two functionalization routes utilize azide and alkyne groups, respectively, and offer simple way to enhance the PVA crosslinking capabilities toward producing new functional polymer-based materials. The Az functionalized PVA was prepared in two steps and denoted by PVA-Az, while Alk functionalized PVA was prepared in one step to produce PVA-Alk. Surfaces modification of PVA by using Az and Alk functional groups was confirmed by spectral analysis (Fourier transform infrared and [sup.13]C-NMR). Results showed that Alk prompted excellent chemical modifications on the surface of PVA while the thermal stability was enhanced by functionalizing the Az and Alk into PVA. Furthermore, X-ray photoelectron spectroscopy investigations showed a successful functionalization and new functional groups addition to PVA surface. Scanning electron microscope images were used to analyze the surface morphology of PVA by incorporating the Az and Alk groups, which indicated rougher surfaces compared to that of PVA backbone. In terms of efficiency and simplicity, the techniques used in this study appear to be entirely satisfactory. KEYWORDS alkyne, azide, click-chemistry, poly (vinyl alcohol), polymer functionalization, surface modification, orcid.org/0000-0002-23106620 orcid.org/0000-0002-9194719X 1 | INTRODUCTION Generally, polymers are classified into two main groups, natural and synthetic polymers. One of the most important subclasses within natural and synthetic polymers is biodegradable [...]

A new chemical treatment method to extract rich cellulosic fibers from date palm agro-residues is developed. The method yielded high-performance natural date palm fibers based on multistep process, which is efficient, sustainable, and unique. The proposed method consists of three steps: dewaxing, acetylation, and mercerization, which are unique in terms of time control and their sequence resulting in optimal properties of extracted fiber. Each step is strictly time-controlled and designed to achieve specific objectives in preparation for the next step. Optimization techniques including design of experiment are used to adjust input parameters so as to obtain optimized output from the treatment method. Two approaches are used for supplying heat during the fiber extraction procedure i.e. conventional heat source and microwave heat source. Experimental characterization of extracted fibers is carried out to determine its mechanical and physical properties. Results showed 32% increase in crystallinity degree of the treated fiber over the untreated one. The new method achieved around five-fold increase in ultimate tensile strength and three-fold increase in elastic modulus. The significant enhancement in properties of treated fibers over untreated counterparts confirms the effectiveness of the new process. [ABSTRACT FROM AUTHOR]

This work targets the development of a pioneering synthetic strategy to modify the surface of lignocellulosic/natural filler material abundant in date palm pedicels by incorporating azide and alkyne moieties with the aid of microwave as a heating source. The novelty of this work is originated from the fact that functionalization was achieved, in both cases, using shorter modification path within short time. The developed technique takes into consideration the environmental regulations by endorsing the use of green chemistry toward fast and simple materials synthesize that can be widely used industrially. The functionalized material can be utilized as an intermediate product for several modern applications such as click chemistry and bio-composite production. The modified materials were characterized using Fourier transform infrared, solid-state 13C nuclear magnetic resonance (ssNMR), x-ray diffraction (XRD), and thermo-gravimetric analysis (TGA). Characterization techniques provide evidence that the functional groups were successfully incorporated in the natural filler which depicts that the used functionalization technique is effective in providing a trouble-free route toward natural filler modification. Thereby, the findings of this work provide a new opportunity for using click chemistry approach to fabricate cost-effective and sustainable bio-composite materials. [ABSTRACT FROM AUTHOR]