Polymers Research Group Prof. Dr. Maria Isabel Felisberti misabel@iqm.unicamp.br Universidade Estadual de ampinas - Unicamp hemistry Institute Biodegradable Polymers Dr. Juliana Aristéia de Lima julima@iqm.unicamp.br 09 September 2009
UNIAMP 41 million UNIAMP 193 million 50.000 inhabitants Department of Physical hemistry Polymers Research Group
Polymer: is a macromolecule composed of repeating structural units typically connected by covalent chemical bonds. While polymer in popular usage suggests plastic, the term actually refers to a large class of natural and synthetic materials with a variety of properties.
Polymers: : 3 types Thermoplastics: are polymers that turn to a liquid when heated and freeze to a glassy state when cooled. Ex: PE, PP, Nylon, PET, PS Elastomers (Rubber): present crosslinks, but the polymer chains are linear and flexible with high elasticity. Ex: NR (nature rubber) Thermosets: formation of cross links between polymer chains that prevents the melting of the material with a new heating. Ex: Epoxy resin, PU foam
Thermoplastics Synthetic Polymers: are essential materials to modern life and are often used in disposable applications, as packaging. This is the origin of a serious problem for the environment. Generally these materials are inert to microbial degradation. There was an increasing in public concern over the harmful effects of petrochemical-derived materials in the environment.
Thermoplastics - Biodegradable Polymers In biological systems, biopolymers degrade mainly by enzymatic hydrolysis and to some extent by oxidation; Biodegradable synthetic polymers have been developed which are safe for use by humans and disposal of polymer waste does not arise; Aliphatic polyesters are one important class of biodegradable polymers as several of them are commercially potential biomaterials.
Biodegradable Polymers: Poly(hydroxybutyrate) - PHB 3 3 H 2 2 n 3 2 H a microbial polyester; accumulated intracellularly by a large number of microorganisms, presenting biodegradability and biocompatibility. PHB production involves a sustainable process related to the sugar cane. Brazil sugar available at low cost and large quantity; technological process available for fermentation in large-scale.
PHB applications: Packaging Biodegradable films Biomaterials Microcapsules of water soluble compounds
PHB disadvantages: 1) high degree of crystallinity in such case is quite brittle material absorption by the body is very slow low rate of biodegradation 2) It may suffer degradation when it is kept for a relatively long time at a temperature above melting point, around 180 Window of processing temperature limited 2 3 3 H 2 3 reaction of thermal degradation 3 2 H 3 2 3
Blends of PHB and epichlorohydrin elastomers PHB - quite brittle material - may suffer thermal degradation epichlorohydrin elastomers can improve the PHB properties PHB/elastomers prepared by casting Even with the immiscibility of the blends and the degradation of PHB phase the elastomeric phase was able to protect the crystalline phase Window of processing temperature limited Lima J A, Felisberti M I. European Polymer Journal, 42 (2006) 602 614.
PHB Spheric rystalline Structure (1) (2) (3) amorphous component 0,5 mm (4) 0,5 mm (5) 0,5 mm (6) affects the formation of spheric crystalline structure 0,5 mm 0,5 mm 0,5 mm (7) (8) (9) To improve the PHB mechanical properties 0,5 mm 0,5 mm 0,5 mm Lima J A, Felisberti M I. European Polymer Journal, 42 (2006) 602 614.
Poly(hydroxybutyrate) Biodegradable Polyurethanes Jonathan Bergamaschi, Maria Isabel Felisberti jonathan@iqm.unicamp.br Poly(p-dioxanone) Synthetic routes Transesterification with Ethylene Glycol Polyols with controlled molecular weight diisocyanate Biodegradable Polyurethanes PHB PPD H 3 n 3 + H H m 3 H H H + n H + H 3 H m Hexamethylene diisocyanate H H H + H + H H H + H H n m n m HDI 3 N N HDI
Synthesis of macromers and polymers from plant oils Sebastián Gómez Robles, Maria Isabel Felisberti sebastiangomezrobles@gmail.com Extraction Plant ils Modification, Synthesis Biomass Degradation, Assimilation Waste Life cycle of polymer based on vegetable oils Use Polymers Triglycerides (Rubber Seed il) modification Macromonomers homopolymerization, copolymerization Polymers, Resins H 2 H H 2 triglycerides H 2 H 2 Monoglyceride bis-maleate half ester Monoglyceride bis-maleate half ester (Macromonomer) (Macromonomer) Styrene Styrene 2 n H 2 m m' 2 2 n'
Amphiphilic Biodegradable opolymers based on Sucrose Methacrylate (MSc) and Acrylic Monomers Heitor Fernando Nunes de liveira, Maria Isabel Felisberti heioliveira@iqm.unicamp.br H H H H H H Sucrose H H R R H Enzimatic atalysis H H H H H MSc-1'H H H Sucrose Methacrylate MSc HN Methyl Methacrylate (MMA) Radical Polymerization N-Isopropylacrilamide (NIPAAm) Poly(MSc-co-MMA) Poly(MSc-co-NIPAAm Poly(MSc) Potentially biocompatible and biodegradable!
Poly(ethylene ethylene-co-vinyl alcohol) - EVH good thermal stability; high chemical resistance; has been used as a food packaging material due to its excellent gas barrier properties and harmlessness toward health; EVH membranes have attracted research interest in fields of biomedical science because of good blood compatibility and water treatment because of its hydrophilicity. Lima J A, Felisberti M I. European Polymer Journal, 44 (2008) 1140 1148.
Lima J A, Felisberti M I. Journal of Membrane Science. doi:10.1016/j.memsci.2009.08.008.. Membranes of poly(ethylene ethylene-co-vinyl alcohol) Ternary solution preparation EVH/PMMA/DMF Phase separation by TIPS process (decrease of the temperature) L-L and S-L phase separation EVH-32/PMMA (a) 20/80 (b) 40/60 EVH rich phase 500μm PMMA rich phase (c) 20/80 (d) 40/60
ellulose acetate - Green polymer From biodegradable polymers could be a solution for environmental problems, substituting the polyolefins in the composites for textile, automotive and other industries, reducing emission of 2. ellulose acetate (A) is a biodegradable polymer made from wood or recycled paper and can be used for substituting polyolefins. A Blends A nanocomposites A modification with ionic liquids
Biodegradable composites of cellulose acetate with lignocellulosic short fiber of urauá Miguel Gutierrez, Maria Isabel Felisberti mgutierrez@iqm.unicamp.br Fiber glass replacement A ellulose Acetate P Plasticizers F uraua s Fiber
A nanocomposites biopolymer-clay nanocomposites Pos doctoral - 2009 Prof. Dr. Maria do armo Gonçalves Prof. Dr. Maria Isabel Felisberti A/PEPi/MMT clay triethyl citrate (TE) dimethyl phthalate (DMP) ionic liquid (IL) as the plasticizer Investigated the structures Twin-screw extrusion compare with the A/PEPi blends
A nanocomposites biopolymer-clay nanocomposites Pos doctoral - 2009 Prof. Dr. Maria do armo Gonçalves Prof. Dr. Maria Isabel Felisberti A/PEPi/MMT clay Acetone Ionic liquids as the solvent Investigated the influence of solvent in the structures Solution intercalation method compare with the A/PEPi blends
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