Shao-Jun Xiong

Bio: Shao-Jun Xiong is an academic researcher from Beijing Forestry University. The author has contributed to research in topics: Biodegradable plastic & Lignin. The author has an hindex of 1, co-authored 3 publications receiving 27 citations.

Economically Competitive Biodegradable PBAT/Lignin Composites: Effect of Lignin Methylation and Compatibilizer

Abstract: In the past 70 years, over 8 billion tons of plastics have been produced, the majority of which cannot be fully biodegraded, causing their fragments to be found everywhere in the biosphere, including living organisms. Herein, a group of biodegradable composites were produced by blending poly(butylene adipate-co-terephthalate) (PBAT) with technical lignin through a twin-screw extrusion method. Two strategies were developed to improve the mechanical properties of PBAT/lignin composites: (1) modifying lignin via methylation to reduce hydrogen bonding between −OH groups and (2) enhancing the intermolecular interactions between PBAT and lignin by adding maleic anhydride-graft-PBAT as a compatibilizer. The composites obtained from the two strategies with 60 wt % lignin contents exhibited ideal tensile performance which could meet the requirement of the Chinese National Standard for packaging. The interactions between different composite components were investigated by morphological and thermal analyses. The results showed that when lignin is used as filler in the composites, the molecular mobility of lignin and the size of its agglomerates remarkably impacted the ductility and mechanical strength of the PBAT/lignin films. A simple cost comparison between neat PBAT film and PBAT/lignin composite films indicated that the latter was economically competitive, and the production costs could significantly reduce by 36%.

Lignin-based biodegradable plastic and preparation method

Abstract: The invention discloses a preparation method of a lignin-based biodegradable plastic. The preparation method includes the steps: synthesizing methylation lignin; synthesizing lignin-based plastic master batch; preparing lignin-based biodegradable plastics. According to the method, the lignin, the methylation lignin and polyadipic acid/polybutylene terephthalate (PBAT) are compounded and modified to prepare lignin-based plastics meeting totally degradable requirements. Methylation modification of part of lignin is implemented and added into compound materials, overall performance of the plastics can be remarkably improved, use of plastic additives is decreased, and the preparation cost of the plastics is effectively reduced, so that market promotion of the plastics is facilitated. The lignin-based biodegradable plastic can be used for production of shopping bag, rubbish bags, mulching films, vegetable greenhouse films, injection molding plate sheets, injection molding sheets and the like.

Rice husk as bio-source of silica: preparation and characterization of silica bio-composites

Abstract: Silica powder has been extracted from rice husk employing a simple extraction procedure for preparing poly(lactic acid) bio-composites with differing filler contents (namely, 5, 10, 20 and 30 wt%). These materials have been obtained through a semi-industrial process of extrusion. The thermal, mechanical and morphological properties have been investigated. Despite a broad distribution of silica particle size, the prepared bio-composites have exhibited improved storage modulus and reduced oxygen permeabilities. The collected values at 10 and 30 wt% have been compared with those of homologous samples prepared using a commercial silica. Two micro-mechanical models (Voigt and Halpin–Tsai) have been used to also fit the mechanical data. Finally, an economic analysis of material and energetic costs has been performed on samples containing silica from rice husk in order to establish if the proposed process is sustainable or advantageous.

Biopolymeric Sustainable Materials and their Emerging Applications

Abstract: Advancements in polymer science and engineering have helped the scientific community to shift its attention towards the use of environmentally benign materials for reducing the environmental impact of conventional synthetic plastics. Biopolymers are environmentally benign, chemically versatile, sustainable, biocompatible, biodegradable, inherently functional, and ecofriendly materials that exhibit tremendous potential for a wide range of applications including food, electronics, agriculture, textile, biomedical, and cosmetics. This review also inspires the researchers toward more consumption of biopolymer-based composite materials as an alternative to synthetic composite materials. Herein, an overview of the latest knowledge of different natural- and synthetic-based biodegradable polymers and their fiber-reinforced composites is presented. The review discusses different degradation mechanisms of biopolymer-based composites as well as their sustainability aspects. This review also elucidates current challenges, future opportunities, and emerging applications of biopolymeric sustainable composites in numerous engineering fields. Finally, this review proposes biopolymeric sustainable materials as a propitious solution to the contemporary environmental crisis. • Use of biopolymers has emerged as a new paradigm of the ecological conservation. • Biopolymeric composites are easily degraded under the possible source of degraded environment. • Biopolymers have found their applications in biomedical, food, electronics, cosmetics and other emerging fields. • Further understanding on their mode of action through this comprehensive review will imparts knowledge.

Recent Advances in the Application of Functionalized Lignin in Value-Added Polymeric Materials

Abstract: The quest for converting lignin into high-value products has been continuously pursued in the past few decades. In its native form, lignin is a group of heterogeneous polymers comprised of phenylpropanoids. The major commercial lignin streams, including Kraft lignin, lignosulfonates, soda lignin and organosolv lignin, are produced from industrial processes including the paper and pulping industry and emerging lignocellulosic biorefineries. Although lignin has been viewed as a low-cost and renewable feedstock to replace petroleum-based materials, its utilization in polymeric materials has been suppressed due to the low reactivity and inherent physicochemical properties of lignin. Hence, various lignin modification strategies have been developed to overcome these problems. Herein, we review recent progress made in the utilization of functionalized lignins in commodity polymers including thermoset resins, blends/composites, grafted functionalized copolymers and carbon fiber precursors. In the synthesis of thermoset resins such as polyurethane, phenol-formaldehyde and epoxy, they are covalently incorporated into the polymer matrix, and the discussion is focused on chemical modifications improving the reactivity of technical lignins. In blends/composites, functionalization of technical lignins is based upon tuning the intermolecular forces between polymer components. In addition, grafted functional polymers have expanded the utilization of lignin-based copolymers to biomedical materials and value-added additives. Different modification approaches have also been applied to facilitate the application of lignin as carbon fiber precursors, heavy metal adsorbents and nanoparticles. These emerging fields will create new opportunities in cost-effectively integrating the lignin valorization into lignocellulosic biorefineries.