0
Article Tier 2 Remediation Sign in to save

Effects of Lignin on the Thermal and Morphological Properties and Damages Mechanisms after UV Irradiation of Polypropylene Biocomposites Reinforced with Flax and Pine Fibres: Acoustic Emission Analysis

Preprints.org 2024 2 citations

AI summary Read the abstract

This is not about microplastic pollution — it is a materials science study examining how lignin content affects the UV aging, thermal degradation, and structural damage of polypropylene composites reinforced with flax and pine wood fibers, evaluated using acoustic emission analysis.

Polymers

Various wood fibres, including pine and flax, are used in wood–plastic composites (WPCs). This paper studies the effect of the lignin content on the morphological and thermal degradation and damage due to the ultraviolet (UV) aging of polypropylene/flax (PP-flax) and polypropylene/pine (PP-pine) fibres composites. Flax and pine fibres exhibited distinct densities of 1.51 and 1.47 g/cm³, respectively, potentially influenced by growth factors and varying compositions of light substances, such as hemicellulose, lignin, and impurities. The thermal decomposition mass loss increased proportionally with the percentage of lignin in the fibre. From 238°C to 390°C, the pine fibre exhibited a 72% mass loss compared to flax fibre, which showed a 54% mass loss, owing to the higher lignin content in pine fibres. Based on differential scanning calorimetry (DSC), the fibre composition affected the material melting temperature. Moreover, DSC curves revealed a higher degree of crystallinity in the case of the PP-flax biocomposite (12%) compared to pure polypropylene (9%) and PP-pine (6%). This result can be attributed to the high content of crystalline components in flax fibres, such as cellulose. Acoustic emissions analysis confirmed that the high lignin content delays degradation and mitigates the appearance of microcracks on the surface of the PP-pine biocomposite. Overall, the study provides valuable data for understanding the UV degradation phenomenon in biocomposites and highlights the influence of fibre composition on material performance.

More Papers Like This

Article Tier 2

A Study of Plant-Filled Polymer Composites Based on Highly Plasticized Polyvinyl Chloride

AI summary Read the abstract

Not relevant to microplastics — this study characterizes the optical, thermal, and mechanical properties of PVC-based composites filled with plant materials (spruce flour, birch flour, rice husk), exploring eco-friendly construction materials without addressing microplastic pollution.

Article Tier 2

Hydrogen-bonded lignin-acrylic copolymer/WPU composites with Integrated UV shielding, antioxidancy and degradability

AI summary Read the abstract

Researchers synthesized a lignin-acrylic copolymer from rice straw waste and blended it with waterborne polyurethane to create a composite film with 43% higher tensile strength, near-total UV blocking, and dramatically improved antioxidant capacity, offering a biodegradable, microplastic-reducing alternative to conventional plastic films.

Article Tier 2

Changes in Wood Plastic Composite Properties After Natural Weathering and Potential Microplastic Formation

AI summary Read the abstract

Researchers studied how wood-plastic composite materials break down during two years of outdoor weathering in Latvia. They found that the composites developed surface cracks and chemical changes relatively quickly, with exposed wood particles suggesting the release of microplastic fragments. The findings challenge the perception of wood-plastic composites as environmentally friendly alternatives, since they may contribute to microplastic pollution over time.

Article Tier 2

“Ultrasonic and Acoustic Emission Study of High Modulus Fibres and Microplastics Based on the Fibres”

AI summary Read the abstract

Researchers measured the mechanical stiffness of high-modulus synthetic fibers and fiber-reinforced microplastic composites using ultrasonic testing across a range of temperatures, providing materials science data relevant to the structural performance of these engineered materials.

Article

Selection of Binding Material for the Manufacture of Polymer Composite Materials Based on Plant Fibers

AI summary Read the abstract

Fabrication trials of plant fiber-reinforced microplastic composites with biodegradable polymer binders found that vinyl acetate copolymers and starch-based binders achieved reinforcement coefficients (Ku=3.2 and 2.5) comparable to conventional epoxy matrices (Ku=3.8). Developing biodegradable polymer composites is directly relevant to microplastic pollution research, as replacing persistent synthetic polymers with biodegradable alternatives reduces long-term microplastic accumulation in the environment.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper