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A Comprehensive Study of Biodegradable Composites for Food Packaging Applications
Published in Arbind Prasad, Ashwani Kumar, Kishor Kumar, Biodegradable Composites for Packaging Applications, 2023
P. Shakti Prakash, Vivek Pandey, Manish Kumar
Due their resistance to degradation, the wastes produced from the plastics create long-term problems (Van den Oever et al. 2017). India generates nearly 5.5 million tons plastic waste per year. An excessive use of plastics causes harmful effects on the environment globally, which tends to increase the requirement of extensive research in the development of eco-friendly as well as biodegradable polymers as new alternate materials (Van den Oever et al. 2017). The biodegradable polymeric materials are manufactured from renewable sources and mimic the properties of traditional polymers such as polyethylene terephthalate (PET), polyethylene (PE), and polypropylene (PP) (Kirwan et al. 2011). Hence, the biodegradable polymers can play a vital role in reducing the negative impacts on environment, which occur due to the high production of plastic and its uses. Moreover, this also leads to a greater potential use of agriculture waste products (Maharana et al. 2009).
Hard Tissue Replacements
Published in Joseph D. Bronzino, Donald R. Peterson, Biomedical Engineering Fundamentals, 2019
Sang-Hyun Park, Adolfo Llinás, and Vijay K. Goel
With external fracture xation, the bone fragments are held in alignment by pins placed through the skin onto the skeleton, structurally supported by external bars. With internal fracture xation, the bone fragments are held by wires, screws, plates, and/or intramedullary devices (Figure 37.1). All the internal xation devices should meet the general requirement of biomaterials, that is, biocompatibility, sucient strength within dimensional constrains, and corrosion resistance. In addition, the device should also provide a suitable mechanical environment for fracture healing. From this perspective, stainless steel, cobalt-chrome alloys, and titanium alloys are most suitable for internal xation. Detailed mechanical properties of the metallic alloys are discussed in the chapter on metallic biomaterials. Most internal xation devices persist in the body aer the fracture has healed, oen causing discomfort and requiring removal. Recently, biodegradable polymers, for example, polylactic acid (PLA) and polyglycolic acid (PGA), have been used to treat minimally loaded fractures, thereby eliminating the need for a second surgery for implant removal. A summary of the basic application of biomaterials in internal xation is presented in Table 37.1. A description of the principal failure modes of internal xation devices is presented in Table 37.2.
Trends in Polymer Applications
Published in Manas Chanda, Plastics Technology Handbook, 2017
Generally, biodegradable polymers are those that can be broken down by nature either by hydrolytic processes or enzymatic processes producing nontoxic by-products. ICI offers a biodegradable plastic under the tradename Bipol. It is a copolyester made from hydroxybutyric and hydroxyvaleric acids. Because of its much higher price than conventional mass polymers, Biopol will not find wide use as long as purely economic considerations determine the use of plastics. A niche market exists, however, for the medical grade of the polymer. For example, fibers can be used for surgical sutures. The compound is absorbed in the body and does not invoke immune reactions. The molecular weight lies between 30,000 and 750,000. The mixture of the two hydroxyacids is produced by a bacterium of the type alcaligenes eutrophus.
Effects of silver nanoparticle on mechanical properties of polylactide composite yarns with different structure
Published in The Journal of The Textile Institute, 2022
Konstantin V. Malafeev, Olga А Moskalyuk, Vladimir Е. Yudin, Elena N. Popova, Elena М. Ivan’kova, Ekaterina М. Gordina, Svetlana А. Bozhkova, Mikko Kanerva
In the last two decades, the number of research works – aimed at the development of biocompatible and biodegradable polymers – has increased considerably. These works are related to solutions of not only medical needs (design of implants, tissue engineering) but also to environmental challenges (environment pollution). Synthetic biodegradable polymers have received considerable attention, particularly, due to the fact that they are approved by United States Food and Drug Administration for biomedical applications (Shameli, 2010). The most popular biodegradable polymers include aliphatic polyesters, such as poly(3-hydroxybutyrate), poly(ε-caprolacton), poly(glycolic acid), and poly(lactic acid) or polylactide (PLA) (Kargarzadeh, 2018; Taylor et al., 1994). It is precisely PLA that is one of the most promising biodegradable polymers, since it possesses biocompatibility, excellent thermal and mechanical properties. PLA is a suitable matrix for preparation of fibrous composites and nanocomposites with various physical and biological properties (Saini et al., 2016). However, this polymer has a partially crystalline structure, which deteriorates the elasticity of PLA-based products; therefore, preparation of elastic materials, as a rule, involves plasticization (Abdelwahab et al., 2012).
Biopolymer composites: a review
Published in International Journal of Biobased Plastics, 2021
Basheer Aaliya, Kappat Valiyapeediyekkal Sunooj, Maximilian Lackner
The biodegradable polymers derived from petrochemical resources are polybutylene succinate (PBS), poly(butylene adipate-co-terephthalate) (PBAT), polyvinyl alcohol (PVA), polyglycolic acid (PGA), and polycaprolactone (PCL). PBS are easily processed semi-crystalline thermoplastic polyesters with acceptable thermo-mechanical properties comparable to PP [77], and thus widely used in bottles and films production. PBS is made up of 1,4-butanediol and succinic acid from renewable resources [14]. The tensile strength (30–35 MPa) of PBS is similar to that of PP and the Young’s modulus (300–800 MPa) is between low-density polyethylene (LDPE) and high-density polyethylene (HDPE) [74]. PBAT belonging to the family of aliphatic-aromatic copolyesters is a biodegradable copolymer of terephthalate and butylene adipate produced by melt polycondensation process [74]. PVA is a hydrophilic semi-crystalline biopolymer exhibiting good mechanical strength and biocompatibility. The properties of PVA make it a promising material for biological as well as industrial applications [63]. PCL is a hydrophobic semi-crystalline aliphatic polyester prepared by ring-opening polymerization of ε-caprolactone. PCL is tough and ductile (elongation at break ~600–800%) and has low glass transition temperature (~ −60°C) and melting temperature (~60°C) [74]. It is mainly used in packaging and biomedical applications.
Biodegradation of Moringa oleifera’s polymer blends
Published in Environmental Technology, 2019
Cristiane Medina Finzi-Quintão, Kátia Monteiro Novack, Ana Cláudia Bernardes-Silva, Thais D. Silva, Lucas E. S. Moreira, Luiza E. M. Braga
Packaging waste is a major contributor to the generation of solid waste in world. The most dominant method of solid waste disposal is landfill followed by composting. The conventional polymers such as low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), poly(ethylene terephthalate) (PET) and poly(vinyl chloride)(PVC) are bio-inert materials. They present a long-time life and can represent an environmental problem due to its difficulty in discarding. Biodegradable polymers represent a way to reduce the amount of plastic waste disposed in landfills [1,2]. Poly(∑-caprolactone) (PCL), polyhidroxybutirate (PBH), poly(lactic acid) (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) are biopolymers that can be used as substitutes of conventional material for production of plastic bags, medicinal products, food packages and others.