Solid Polymer Waste Materials for Repairing of Heritage Composite Structure: An Additive Manufacturing Approach

Currently, plastics and rubbers are broadly being used to produce a wide range of products for several applications like automotive, building and construction, material handling, packaging, toys, etc. However, their waste (materials after their end of life) do not degrade and remain for a long period of time in the environment. The increase of polymeric waste materials’ generation (plastics and rubbers) in the world led to the need to develop suitable methods to reuse these waste materials and decrease their negative effects by simple disposal into the environment. Combustion and landfilling as traditional methods of polymer waste elimination have several disadvantages such as the formation of dust, fumes, and toxic gases in the air, as well as pollution of underground water resources. From the point of energy consumption and environmental issues, polymer recycling is the most efficient way to manage these waste materials. In the case of rubber recycling, the waste rubber can go through size reduction, and the resulting powders can be melt blended with thermoplastic resins to produce thermoplastic elastomer (TPE) compounds. TPE are multi-functional polymeric materials combining the processability of thermoplastics and the elasticity of rubbers. However, these materials show poor mechanical performance as a result of the incompatibility and immiscibility of most polymer blends. Therefore, the main problem associated with TPE production from recycled materials via melt blending is the low affinity and interaction between the thermoplastic matrix and the crosslinked rubber. This leads to phase separation and weak adhesion between both phases. In this review, the latest developments related to recycled rubbers in TPE are presented, as well as the different compatibilisation methods used to improve the adhesion between waste rubbers and thermoplastic resins. Finally, a conclusion on the current situation is provided with openings for future works.

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Processing and Recycling of thermoplastic polymers: Current Scenario and Future Challenges

Turkish Journal of Computer and Mathematics Education (TURCOMAT) ◽

10.17762/turcomat.v12i2.2303 ◽

2021 ◽

Vol 12 (2) ◽

pp. 2744-2753

Author(s):

Balwant Singh, Et. al.

Keyword(s):

Additive Manufacturing ◽

Low Cost ◽

Waste Recycling ◽

Recycling Process ◽

Thermoplastic Polymers ◽

Polymer Waste ◽

Chemical Structures ◽

Future Challenges ◽

Current Scenario ◽

Manufacturing Technologies

Thermoplastic polymers are extensively utilized in electronics, aerospace, automobile and additive manufacturing industries due to low cost, low temperature processing and reusability. Thermoplastics of different grades and chemical structures arereadily available in the market They can be reusedand reshaped, and also can be manufactured with less weight proportion as compared to the metals and ceramics by providing same strength of material. As a result, the plastics products in the market are getting popular day by day with high demand of customized products due to inception of additive manufacturing technologies. In any case, the issue of recycling these materials is challenge due to enormous energy requirements and varying chemical composition of different polymers. There are both mechanical and financial issues that restrict the advancements in this field. The recycling process of polymers can be done by the four different ways such as primary recycling process, secondary recycling process, tertiary recycling process and quaternary recycling process which can be discussed in this systematic review with practical examples. The modifications and implementation of these polymer waste recycling techniques could help to reduce wastage and save material cost which would directly affect the economy of contemporary industries.

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Evaluation of a polymer-steel laminated sheet composite structure produced by friction stir additive manufacturing (FSAM) technology

Polymer Testing ◽

10.1016/j.polymertesting.2020.106690 ◽

2020 ◽

Vol 90 ◽

pp. 106690 ◽

Cited By ~ 4

Author(s):

H. Aghajani Derazkola ◽

F. Khodabakhshi ◽

A. Simchi

Keyword(s):

Additive Manufacturing ◽

Composite Structure ◽

Friction Stir

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Composites from renewable and sustainable resources: Challenges and innovations

Science ◽

10.1126/science.aat9072 ◽

2018 ◽

Vol 362 (6414) ◽

pp. 536-542 ◽

Cited By ~ 173

Author(s):

Amar K. Mohanty ◽

Singaravelu Vivekanandhan ◽

Jean-Mathieu Pin ◽

Manjusri Misra

Keyword(s):

Composite Materials ◽

Composite Structure ◽

Mechanical Performance ◽

Waste Materials ◽

Sustainable Resources ◽

Global Sustainability ◽

Biodegradable Composites ◽

Technological Advances ◽

Plastic Materials ◽

Biobased Content

Interest in constructing composite materials from biosourced, recycled materials; waste resources; and their combinations is growing. Biocomposites have attracted the attention of automakers for the design of lightweight parts. Hybrid biocomposites made of petrochemical-based and bioresourced materials have led to technological advances in manufacturing. Greener biocomposites from plant-derived fiber and crop-derived plastics with higher biobased content are continuously being developed. Biodegradable composites have shown potential for major uses in sustainable packaging. Recycled plastic materials originally destined for landfills can be redirected and repurposed for blending in composite applications, thus leading to reduced dependence on virgin petro-based materials. Studies on compatibility of recycled and waste materials with other components in composite structure for improved interface and better mechanical performance pose major scientific challenges. This research holds the promise of advancing a key global sustainability goal.

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