Thermoset Materials - PowerPoint PPT Presentation

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Thermoset Materials

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... are Formed Crosslinking as Polymers are Formed Thermoset Types Melamine Plastics Crosslinking as Polymers are Formed Polyester Thermosets (TS) ... – PowerPoint PPT presentation

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Title: Thermoset Materials


1
Thermoset Materials
  • MFG 355

2
Introduction
  • Thermoplastics vs Thermosets
  • Thermal properties
  • Strength
  • Uses
  • Processing

3
Viscosity and Thermal Control during Crosslinking
4
General Properties of Thermosets
  • Strength
  • Flexibility
  • Thermal
  • Creep
  • Ability to reinforce
  • Ability to cure at room temperature

5
Formaldehyde Resins
  • Phenolic
  • Urea formaldehyde
  • Melamine formaldehyde

6
Crosslinking
  • Reactive GroupsPhenolics

Plus
7
Thermoset Types
  • Phenolics

8
Crosslinking
  • Reactive GroupsAmino plastics

Plus
Amine
9
Amine plastics clear adhesive
Chipboard
10
Crosslinking as Polymers are Formed
Plus
11
Crosslinking as Polymers are Formed
Melamine Formaldehyde
Water
12
Thermoset Types
  • Melamine Plastics

13
Crosslinking as Polymers are Formed
Water
Melamine Formaldehyde
14
Polyester Thermosets (TS) or Unsaturated
Polyesters (UP)
  • Largest group of thermosets
  • Most like to be reinforced with fiberglass

15
Crosslinking
  • Reactive GroupsUnsaturated polyesters

Plus
Carbon-carbon Double bond
Initiator (usually peroxide)
16
Thermoset Types
  • Unsaturated Polyesters

17
Crosslinking Mechanism for Thermoset Polyesters
Polyester
Styrene (large quantities)
Peroxide
18
Crosslinking Heat
19
Crosslinking Approach of styrene
20
Crosslinking bond to styrene
When styrene's double bond breaks, one end forms
a free radical
Half of peroxide bonds with other end of broken
styrene molecule
21
Crosslinking approach to polymer
Styrene free radical causes the polymer's double
bond to break and allows it to accept a new pi
bond
22
Crosslinking bonding to polymer
New free radical
New bond
Problems Polymers not lined up, steric
interference
Solution Styrene
23
Crosslinking approach of styrene
24
Crosslinking activation of styrene
Styrene's double bond opens, allowing two new
free radical sites
25
Crosslinking bonding of styrene
New bond
Double bond opens but can't create a bond with
any other open bond because of steric effects
Problems Polymers still not lined up, steric
interference
Solution Still more styrene
26
Crosslinking bonding of 2nd styrene
Free radical
New bond
27
Crosslinking bonding with 2nd polymer
Up to 8 styrenes might be needed in the bridge
New bond
28
Crosslinking bonding with 2nd polymer
Etc.
29
Crosslinking more styrene
30
Crosslinking more styrene
31
Crosslinkingbonding to 3rd polymer
32
Laminating Resins
33
Additives to Thermoset Polyesters
Fillers like Calcium Carbonate
Tougheners like rubbers
Antioxidants and UV stabilizers
Reinforcements
34
Molding Compounds
35
Molding Compounds
36
Crosslinking
  • Reactive GroupsEpoxies

Plus
Epoxy Rings
Hardener (amine shown)
37
Thermoset Types
  • Epoxies

38
Vinyl Esters (VE)
39
Polyimides
Carbon-carbon Double bond Imide
Condensation Imide
React with addition reaction
40
Thermoset Types
  • Imides

41
Crosslinking
  • Reactive GroupsPolyurethanes

Plus
Diisocyanates
Polyols
42
Thermoset Types
  • Polyurethanes

43
Crosslinking Between two Existing Polymer Chains
44
Thank You
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