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Bionanocomposites, Their Processing, and Environmental Applications
Published in Shakeel Ahmed, Saiqa Ikram, Suvardhan Kanchi, Krishna Bisetty, Biocomposites, 2018
Sagar Roy, Chaudhery Mustansar Hussain
Several varieties of polycarbonates prepared from different monomers are of great interest. Trimethylene carbonate is used as the monomer during the synthesis of poly(trimethylene carbonate) (PTMC) via ring-opening polymerization technique in the presence of diethylzinc as the reaction catalyst. The polymer alone exhibits very poor mechanical properties, thus copolymerized with several other monomers, such as glycolide and dioxanone, to obtain the desired characteristics. Another variety of polycarbonate is poly(propylene carbonate) (PPC), synthesized via copolymerization of propylene oxide and carbon dioxide. The polymer enhances compatibility and impact resistance. However, biodegradability is quite poor and can be improved through blending with other suitable polymers. Introduction of other polymers may decrease crystallinity, which enhances its susceptibility to enzymatic and microbial attacks.
Degradation Studies of Biodegradable Composites
Published in Arbind Prasad, Ashwani Kumar, Kishor Kumar, Biodegradable Composites for Packaging Applications, 2023
The conversion of CO2 into polymeric polymers provides a potential greenhouse gas recycling alternative. Polypropylene carbonate (PPC) is made by copolymerizing carbon dioxide with propylene oxide. The biological breakdown of PPC is aided by high temperatures. After 6 months, a total mass loss of just 3.2% was detected in garden soil (Du, L.C et al., 2004). A mass loss of 8% was recorded at 40°C in a composting setting, followed by a significant rise in disparity (Bahramian et al., 2016). After only 3 months in an industrial composting operation (at 60°C), a full absolute mass loss may be recorded (Luinstra, 2008).
Development of biomimetic electrospun polymeric biomaterials for bone tissue engineering. A review
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Sugandha Chahal, Anuj Kumar, Fathima Shahitha Jahir Hussian
Chitosan is difficult to electrospun because chitosan has rigid D-glucosamine repeat units, high crystallinity and ability to form hydrogen bond which leads to poor solubility in common organic solvents [92]. Chitosan is attractive as a bone scaffold material because it supports the attachment and proliferation of osteoblast cells as well as formation of mineralized bone matrix [93]. Chitosan nanofibers can be produced by electrospinning process by using acetic acid as solvent [94]. Haider et al. [95] fabricated the very narrow and highly aligned bead free chitosan nanofibers using electrospinning process. Recently, various composite nanofibers of chitosan as base material are reported intended for bone tissue engineering i.e. Jing et al. [96] fabricated the aligned poly (propylene carbonate)/chitosan composite nanofibers; chitosan/PVA nanofibers were prepared using multi-carboxylic acids as environment friendly solvent via electrospinning [93,97]. Silica nanoparticles reinforced chitosan nanofibrous scaffold was prepared for bone tissue engineering; the results revealed that silica nanoparticles improved the mechanical properties, biodegradability, and bone-forming ability [98].