chapt_12_polymers - Chapter 12 Polymers 7/7/10 What is a...

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

View Full Document Right Arrow Icon
7/7/10 Chapter 12 Polymers
Background image of page 1

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

View Full DocumentRight Arrow Icon
7/7/10 What is a polymer? Poly mer many repeat unit C C C C H H H H H H H Polyethylene (PE) C l C l C l C C C C H H H H Polyvinyl chloride (PVC) H H H H Polypropylene (PP) C C C H 3 H C H 3 C H 3 repeat unit repeat unit repeat unit
Background image of page 2
7/7/10 Ancient Polymer History Originally natural polymers were used Wood – Rubber Cotton – Wool Leather – Silk Polymer; hydrogen + Carbon = hydrocarbons Intramolecular bonds are covalent (sharing of electrons)
Background image of page 3

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

View Full DocumentRight Arrow Icon
7/7/10 Polymer Composition Most polymers are hydrocarbons i.e. made up of H and C Saturated hydrocarbons Each carbon bonded to four other atoms CnH2n+2 C C H H H H H H
Background image of page 4
7/7/10
Background image of page 5

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

View Full DocumentRight Arrow Icon
7/7/10 Unsaturated Hydrocarbons Double & triple bonds relatively reactive – can form new bonds Double bond – ethylene - CnH2n 4-bonds, but only 3 atoms bound to C’s Triple bond – acetylene - CnH2n-2 C C H H H H C C H H
Background image of page 6
7/7/10 77 Polymers – Molecular Shape Conformation – Molecular orientation can be changed by rotation around the bonds note: no bond breakig needed
Background image of page 7

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

View Full DocumentRight Arrow Icon
Click to edit Master subtitle style 7/7/10 Figure 12.8 The length of kinked molecular chain is given by Equation 12.4, due to the
Background image of page 8
7/7/10 Covalent chain configurations and strength: Direction of increasing strength Molecular Structures B ranch ed Cross- Linked Netw ork Line ar second ary bond ing
Background image of page 9

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

View Full DocumentRight Arrow Icon
7/7/10 Copolymers two or more monomers polymerized together random – A and B randomly vary in chain alternating – A and B alternate in polymer chain block – large blocks of A alternate with large blocks of B graft – chains of B grafted on to A backbone A – B –
Background image of page 10
7/7/10 1111 Polymer Crystallinity Ex: polyethylene unit cell Crystals must contain the polymer chains in some way Chain folded structure 10 nm
Background image of page 11

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

View Full DocumentRight Arrow Icon
7/7/10 Polymer Crystallinity Polymers rarely 100% crystalline Too difficult to get all those chains aligned % Crystallinity : % of material that is crystalline. --
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 07/07/2010 for the course CHEM 3302 taught by Professor ... during the Spring '10 term at University of Minnesota Morris.

Page1 / 37

chapt_12_polymers - Chapter 12 Polymers 7/7/10 What is a...

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