Give an example of biodegradable aliphatic polyester

Aliphatic Polyester The aliphatic polyester (b) is PLA consisting of l-lactic acid and/or d-lactic acid units. From: Biopolymers: Processing and Products, 2015 Related terms: • Biopolymer • Ring Opening Polymerization • Hydrolysis • Polymerization • Starch • Polyhydroxyalkanoate • Molecular Weight • Polyesters • Caprolactone • Monomer Hyperbranched aliphatic polyesters 2 have been commercialized only in recent years. These materials are prepared by adding portions of 2,2-dihydroxymethylpropionic acid (BisMPA=AB 2-monomer) to a 1,1,1-trishydroxymethylpropane core molecule (=B 3-core) under acidic catalysis (Malmström 1995). Via this procedure hyperbranched aliphatic polyesters with molecular weights in the range of 1000–2000 and degrees of branching of 50% (Burgath 2000) are obtained. Hydroxyl functionalities vary between 5 and 30. Although the molecular weights are considerably smaller than published initially, these hyperbranched aliphatic polyesters are considered to be useful for coatings, paints, and resins and as rheology modifiers as well as processing additives for other polymers (Mackey 2000). Numerous studies on chemical modification and behavior of the aliphatic polyesters have been published. The hyperbranched aliphatic polyester–polyols are sold under the trade name Boltorn® by Perstorp AB, Sweden ( Scheme 2 Fluid Loss Additives Johannes Karl Fink, in Petroleum Engineer's Guide to Oil Field Chemicals and Fluids, 2012 Polyorthoesters Aliphatic polyesters degrade...

See the figure given below and select the correct statements regarding polymers: 1. Figure X shows structure of a monomer while figure (Y) shows structure of a polymer 2. Small boxes in the structure represent monomers which are joined to give a polymer 3. Figure (x) shows structure of a linear polymer while (Y) shows structure of a cross-linked polymer

The interest in producing biodegradable polymers by chemical treatment, microorganisms and enzymes has increased to make it easier to dispose after the end of its use without harming the environment. Biodegradable polymers reported a set of issues on their way to becoming effective materials. In this article, biodegradable polymers, treatment, composites, blending and modeling are studied. Environmental fate and assessment of biodegradable polymers are discussed in detail. The forensic engineering of biodegradable polymers and understanding of the relationships between their structure, properties, and behavior before, during, and after practical applications are investigated. Disposal of plastic wastes is a serious environmental problem that we face today. Mass production and increased use of plastics in wide applications in our daily life Biodegradable polymers are materials that can work for a limited time before degrading into readily discarded products through a regulated procedure 2O, CO 2, and methane. The biodegradation process depends on the material’s composition The biodegradable plastics industry is highly promising. However, they need to be developed in tandem thorough examination of end-of-life processes of treatment and a worldwide integration with organic management of waste as selective biowaste collection expands. Biodegradable plastics have the benefit of being able to be handled biologically at the end of their lives (composting or anaerobic digestion). ...

Aliphatic polyesters are biodegradable polymers used in biomedical and pharmaceutical engineering. It may be helpful to introduce a few foundational terms to clarify the chemical makeup of aliphatic polymers: • Polymers are relatively large molecules containing repeating subunits. For reference, proteins are polymers that consist of repeating amino acid subunits. • Aliphatic molecules exist as a long chain rather than an aromatic ring • Polyester molecules consist of multiple repeating ester groups • An ester group comprises a carbon atom that is double-bound to an oxygen atom, single-bound to a carbon atom, and single-bound to an oxygen atom that is also single bound to another carbon atom Aliphatic polyesters are made up of repeating ester units. Aliphatic polyesters are biodegradable polymers widely used in biomedical and pharmaceutical engineering. Polymers are large molecules containing repeating subunits, and polyesters consist of repeating ester groups. Aliphatic molecules exist in a long straight chain rather than a ring. Therefore, aliphatic polyesters are long-chain molecules with repeating ester groups. Ester groups are made of a carbon atom that is double-bound to an oxygen atom, single-bound to a carbon atom, and single-bound to an oxygen atom that is also single-bound to another carbon atom. Aliphatic polyesters are produced from naturally-occurring compounds like lactide, glycolide, and caprolactone. They are used to create scaffolds for tissue engineering, ...

Biodegradable Polyester PLGA is a biodegradable polyester that undergoes bulk hydrolysis, facilitating a sustained release of cargo, with the degraded products easily removed by the citric acid (Krebs) cycle [107]. From: Bone Repair Biomaterials (Second Edition), 2019 Related terms: • Starch • Polyhydroxyalkanoate • Molecular Weight • Polyesters • Polyhydroxybutyrate • Aliphatic Polyester • Caprolactone • Dendrimer • Monomer Polycondensation S. Agarwal, in Polymer Science: A Comprehensive Reference, 2012 5.15.5Biodegradable Polyester Nanoparticles A lot of literature is available on the use of aliphatic polyesters for drug delivery applications. Aqueous suspensions of biodegradable polyesters, mainly PCL, PLA, and copolymers, have been extensively studied for this purpose. 118 Suspensions of polyester nanoparticles are obtained as secondary suspensions, for example, by solvent displacement method, emulsion, double emulsion, and salting out methods. The method selected is dependent on the size and loading efficiency required for different biomedical applications. Biodegradable particle dispersion provides not only the advantage of encapsulation of drug molecules but interestingly a reduction in biodegradation time by a factor of 10 3 for PCL nanoparticles as compared to the film as shown by Gan et al. 119 Only a few studies have reported on the use of condensation polyesters for the formation of aqueous dispersions (nano/microparticles in water) for different aims. Bikiaris...

Biodegradable Polyester PLGA is a biodegradable polyester that undergoes bulk hydrolysis, facilitating a sustained release of cargo, with the degraded products easily removed by the citric acid (Krebs) cycle [107]. From: Bone Repair Biomaterials (Second Edition), 2019 Related terms: • Starch • Polyhydroxyalkanoate • Molecular Weight • Polyesters • Polyhydroxybutyrate • Aliphatic Polyester • Caprolactone • Dendrimer • Monomer Polycondensation S. Agarwal, in Polymer Science: A Comprehensive Reference, 2012 5.15.5Biodegradable Polyester Nanoparticles A lot of literature is available on the use of aliphatic polyesters for drug delivery applications. Aqueous suspensions of biodegradable polyesters, mainly PCL, PLA, and copolymers, have been extensively studied for this purpose. 118 Suspensions of polyester nanoparticles are obtained as secondary suspensions, for example, by solvent displacement method, emulsion, double emulsion, and salting out methods. The method selected is dependent on the size and loading efficiency required for different biomedical applications. Biodegradable particle dispersion provides not only the advantage of encapsulation of drug molecules but interestingly a reduction in biodegradation time by a factor of 10 3 for PCL nanoparticles as compared to the film as shown by Gan et al. 119 Only a few studies have reported on the use of condensation polyesters for the formation of aqueous dispersions (nano/microparticles in water) for different aims. Bikiaris...

The interest in producing biodegradable polymers by chemical treatment, microorganisms and enzymes has increased to make it easier to dispose after the end of its use without harming the environment. Biodegradable polymers reported a set of issues on their way to becoming effective materials. In this article, biodegradable polymers, treatment, composites, blending and modeling are studied. Environmental fate and assessment of biodegradable polymers are discussed in detail. The forensic engineering of biodegradable polymers and understanding of the relationships between their structure, properties, and behavior before, during, and after practical applications are investigated. Disposal of plastic wastes is a serious environmental problem that we face today. Mass production and increased use of plastics in wide applications in our daily life Biodegradable polymers are materials that can work for a limited time before degrading into readily discarded products through a regulated procedure 2O, CO 2, and methane. The biodegradation process depends on the material’s composition The biodegradable plastics industry is highly promising. However, they need to be developed in tandem thorough examination of end-of-life processes of treatment and a worldwide integration with organic management of waste as selective biowaste collection expands. Biodegradable plastics have the benefit of being able to be handled biologically at the end of their lives (composting or anaerobic digestion). ...

Aliphatic Polyester The aliphatic polyester (b) is PLA consisting of l-lactic acid and/or d-lactic acid units. From: Biopolymers: Processing and Products, 2015 Related terms: • Biopolymer • Ring Opening Polymerization • Hydrolysis • Polymerization • Starch • Polyhydroxyalkanoate • Molecular Weight • Polyesters • Caprolactone • Monomer Hyperbranched aliphatic polyesters 2 have been commercialized only in recent years. These materials are prepared by adding portions of 2,2-dihydroxymethylpropionic acid (BisMPA=AB 2-monomer) to a 1,1,1-trishydroxymethylpropane core molecule (=B 3-core) under acidic catalysis (Malmström 1995). Via this procedure hyperbranched aliphatic polyesters with molecular weights in the range of 1000–2000 and degrees of branching of 50% (Burgath 2000) are obtained. Hydroxyl functionalities vary between 5 and 30. Although the molecular weights are considerably smaller than published initially, these hyperbranched aliphatic polyesters are considered to be useful for coatings, paints, and resins and as rheology modifiers as well as processing additives for other polymers (Mackey 2000). Numerous studies on chemical modification and behavior of the aliphatic polyesters have been published. The hyperbranched aliphatic polyester–polyols are sold under the trade name Boltorn® by Perstorp AB, Sweden ( Scheme 2 Fluid Loss Additives Johannes Karl Fink, in Petroleum Engineer's Guide to Oil Field Chemicals and Fluids, 2012 Polyorthoesters Aliphatic polyesters degrade...

See the figure given below and select the correct statements regarding polymers: 1. Figure X shows structure of a monomer while figure (Y) shows structure of a polymer 2. Small boxes in the structure represent monomers which are joined to give a polymer 3. Figure (x) shows structure of a linear polymer while (Y) shows structure of a cross-linked polymer

Aliphatic polyesters are biodegradable polymers used in biomedical and pharmaceutical engineering. It may be helpful to introduce a few foundational terms to clarify the chemical makeup of aliphatic polymers: • Polymers are relatively large molecules containing repeating subunits. For reference, proteins are polymers that consist of repeating amino acid subunits. • Aliphatic molecules exist as a long chain rather than an aromatic ring • Polyester molecules consist of multiple repeating ester groups • An ester group comprises a carbon atom that is double-bound to an oxygen atom, single-bound to a carbon atom, and single-bound to an oxygen atom that is also single bound to another carbon atom Aliphatic polyesters are made up of repeating ester units. Aliphatic polyesters are biodegradable polymers widely used in biomedical and pharmaceutical engineering. Polymers are large molecules containing repeating subunits, and polyesters consist of repeating ester groups. Aliphatic molecules exist in a long straight chain rather than a ring. Therefore, aliphatic polyesters are long-chain molecules with repeating ester groups. Ester groups are made of a carbon atom that is double-bound to an oxygen atom, single-bound to a carbon atom, and single-bound to an oxygen atom that is also single-bound to another carbon atom. Aliphatic polyesters are produced from naturally-occurring compounds like lactide, glycolide, and caprolactone. They are used to create scaffolds for tissue engineering, ...