biomaterialspolymers2008F

biomaterialspolymers2008F - Spring 2010-Polymers in...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
Click to edit Master subtitle style CHEE 311 Pharm 610J.S. Parent Spring 2010-Polymers in medicine 11 Nasser-Eddin M., Ph.D
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B. Amsden Pharm 610CHEE 340 Polymer Biomaterials There are a large number of uses for polymers in the biomaterials field. These arise due to the wide variety of properties possible. OBJECTIVES § to introduce some fundamental polymer properties and the factors that influence them § to provide an overview of the uses of polymers as biomaterials § Case study: Biodegradable polymers 22
Background image of page 2
B. Amsden Pharm 610CHEE 340 POLYMERS Polymers - long chain molecules of high molecular weight -(CH2)n- 33 Obj10
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B. Amsden Pharm 610CHEE 340 Common Polymer Biomaterials 44
Background image of page 4
B. Amsden Pharm 610CHEE 340 Advantages and required properties The main advantages of the polymeric biomaterials compared to metal or ceramic materials are ü Ease of manufacturability to produce various shapes (latex, film, sheet, fibers, etc.), ü Ease of secondary processability ü Reasonable cost, ü Availability with desired mechanical and physical properties. The required properties of polymeric biomaterials are similar to other biomaterials (detailed in part II): ü Biocompatibility ü Sterilizability, ü Adequate mechanical and physical properties, ü Manufacturability 55
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B. Amsden Pharm 610CHEE 340 Requirements 66
Background image of page 6
B. Amsden Pharm 610CHEE 340 Properties Part I 77
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B. Amsden Pharm 610CHEE 340 88 Drawback of condensation polymerization : ü Tendency for the reaction to cease before the chainsgrow to a sufficient length due to the decreased mobility of the chains and reactant chemical species as polymerization progresses. ü Result= short chains. However, in the case of nylon the chains are polymerized to a sufficiently large extent before this occurs and the physical properties of the polymer are preserved. Natural polymers, such as polysaccharides and proteins, are also made by condensation polymerization. The condensing molecule is always water (H2O).
Background image of page 8
B. Amsden Pharm 610CHEE 340 Properties: Molecular weight synthetic polymers possess a molecular weight distribution M i N i Obj101 Obj102 polydispersity index = Mw/Mn
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B. Amsden Pharm 610CHEE 340 The Bulk State : Solid Polymers can be either amorphous or semi-crystalline, or can exist in a glassy state. amorphous glassy state § hard, brittle § no melting point semi-crystalline glassy state § hard, brittle § crystal formation when cooled § exhibit a melting point 1010
Background image of page 10
B. Amsden Pharm 610CHEE 340 The glass transition is the temperature where the polymer goes from a hard, glass like state to a rubber like state. related to chain mobility § increased flexibility, lower Tg factors : § flexible links in backbone § interaction between chains Plasticizers* interfere with bonding, increase chain movement, decrease Tg 1111 Plasticizers or dispersants are additives that increase the plasticity or fluidity of the material to which they are added
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B. Amsden Pharm 610CHEE 340 Tg effect of Molecular weight § Fox-Flory eqn. K = constant for given polymer
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/07/2011 for the course MECH 633 taught by Professor Mohammadnasserdine during the Spring '10 term at American University of Beirut.

Page1 / 91

biomaterialspolymers2008F - Spring 2010-Polymers in...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online