Cyclic polyesters could improve the properties of degradable plastics, but routes to them that provide a product with faster rates, higher molar mass, and greater selectivity for cyclic vs linear p...

Precise structure-property relation of a biodegradable polymer (e.g., aliphatic polyester) is anticipated only if monomer units and chiral centers are arranged in a defined primary sequence as a biomacromolecule. An emerging synthetic methodology, namely segmer assembly polymerization (SAP), is introduced in this paper to reveal the latest progress in polyester synthesis. Almost any periodic po...

The spinning limit for three different fibres (cotton, viscose rayon and polyester) on a Dref-3 friction spinning machine has been investigated. The change in yarn properties with progressive change in count has also been reported. The count range has been seen to be dependent on fibre type. As one progresses from very coarse to fine counts, the yarn tensile property remain fairly unaltered for...

This paper describes recent progress made in the use of high pressure or supercritical fluids to process polymers into three-dimensional tissue engineering scaffolds. Three current examples are highlighted: foaming of acrylates for use in cartilage tissue engineering; plasticization and encapsulation of bioactive species into biodegradable polyesters for bone tissue engineering; and a novel las...

The potential of bio based plastics for replacement of petrochemical plastics is 90%, corresponding to 240 million tons per year.1 Bio-based materials such as polynucleotides, polyamides, polysaccharides, polyoxoesters, polythioesters, polyanhydrides, polyisoprenoids and polyphenols are potential candidates for substitution of synthetic plastics.2 Polyhydroxyalkanoates (PHAs), belonging the gro...

The introduction of long-chain branched structures into biodegradable polyesters can effectively improve the melt strength and blow-molding properties polyesters. In this study, pentaerythritol (PER) was used as a branching agent to synthesize poly(butylene dodecanedioate) (PBD), resulting polymers were characterized by Nuclear Magnetic Resonance Proton Spectra (1H NMR) Fourier Transform Infrar...

The growing awareness of environmental concerns and the fossil resources depletion have raised need to develop sustainable degradable polymers such as aliphatic polyesters. γ-Lactone-based polyesters are great interest today due their ability depolymerize. introduction functional groups appeared also useful tune properties This can be addressed by use monomers sugar-based α-hydroxy-γ-butyrolact...