Complex parts in one operation
7 h3 j$ H" e0 l' C
Wide range of properties
6 g, T7 F& v! F0 r9 M4 e1 CColoring
. U( R [9 U B/ b- V" y3 ]6 bLow energy requirements
9 a7 G3 i( g( i; R
Good insulators
! \% P2 j# @: b% \( l' r) \, PLow cost & weight
' l7 i7 P2 a$ H1 Y$ C3 n+ S3 ]' e& @ c( qResistance to chemicals
! e0 M* @" n! M/ o, ^5 j4 h
From monomers to polymers
7 F0 ~* q& u' q" F1 E4 N" O
Examples : (in between   : monomer )
6 l" F0 m* M) z& D* M0 ?Polyethylene: (catalytic polymerization of ethylene gas under high pressure)
/ x( b2 H3 T$ p5 K6 @4 m9 M* n0 ], l —CH2 — CH2-- CH2 — CH2 -- CH2 —
% u2 x% f: }$ {, v
Polypropylene: (catalytic polymerization of propylene gas under pressure)
. i: k- L( U) r' g/ u5 L3 {0 a' }
—CH2 — CH-- CH2 — CH -- CH2 —
, N) M, {6 n+ P5 ]
CH3 CH3
4 e- a5 K: K& X2 R. KPolyvinylchloride :
! h, f+ n! _) i( c( X
— CH2 — CHCl -- CH2 — CHCl -- CH2 — CHCl —
( K# b l) Z# Q3 O! \, y, V" F% U8 S
Molecular weight
/ }, e9 e7 W& j! b4 l
. F2 F6 H% n" q! |4 u1 M
0 ]6 `6 D% V1 z2 J0 V$ Y, r6 p
0 m: Z' S7 p* c: D" o. p, T4 Y
Polymer structures
7 H$ B" k7 F! m& E; c6 ^
Homopolymers (ie PP homo)
: v, f' A0 t {& n' \; m: lCopolymers (ABS, SAN)
; v8 ]6 O. H! J+ E5 `
random
3 Y, ^. H+ c0 n/ Iregular
) v) g' Y! }+ l' X! A0 x7 x6 `
sequenced
3 P+ X c# Z* |" z. h0 F' w' {# k glinear
X3 R \6 i) G4 Ggrafted
* X. M C& N0 D* r) p6 T
Blends and alloys
- ^4 {+ o8 t. C8 _
8 w: q7 ]% C) K$ IPolymer structures
) c' [2 a$ b5 E3 h: x; \Why using Blends and alloys?
5 t/ G2 E1 k& ^& n- s
To combine properties of different polymers.
8 a' e/ g, ]3 s
Examples: what brings each polymer in blends below?
1 P! S2 |* @# q, e- W8 C
ABS/PC
. _9 Z0 l" w/ u) V! R% wPC/PBT
" z) G1 [% Y E0 V cPPO/PS
& p4 @4 M+ l& g2 CPA/PPO
/ c u; j% y I9 y% n" X7 n
. k' e$ g( @/ P6 aPolymer structures
6 R# ~4 P" q7 n4 m( I3 h
0 `. o) P( t. E! p4 p6 PCrystalline vs Amorphous resin
* g2 n6 y3 q' _% G, }Are the resin different?
+ H& \* l7 h' }& v7 f4 z# iAre the resin processed the same way?
# u0 W" G5 m; ^2 x% cCan the resin be used in the same applications?
- B- ? D+ D7 {; T: z
6 c+ d( Q9 ?6 x: X J/ P' `Amorphous resin
8 D8 Z; g2 q7 i: _+ M
Non organized structure
/ J i% j3 S+ \4 O W& r
Broad softening range: 20°C
R3 A) g& E% x
High viscosity usually
4 m9 H% n( M1 tPoor chemical properties in general
5 h+ D6 d- }, D1 Q$ k) A
Can be transparent
2 F4 j' h% U- s9 Z! H1 l9 J( N
/ \6 ~( ?1 c, t2 J/ F2 mAmorphous resin
9 J" \+ A, b. O2 n( B' s) a
; C/ T, d# r! i) ?, p! r c$ p8 h
, Q5 k9 s! O" p( T& a
) A/ l7 V8 s# Y4 Y7 f! S
Crystalline resin
4 V" d7 W C4 O+ }" QOrganized structure
7 \$ W+ F& d- N0 F) H6 s! i! b/ ]5 m! b' }+ \+ I
' m+ I6 i9 N3 X0 k
+ V. U& Y4 y: i# lMelting point: within 5°C
) k9 l- t" u! T( |0 d5 j& x; ]
Low viscosity usually
! O. X$ p& V( {5 q; H0 x
Good chemical properties in general
! E/ d& y* J/ y0 dUsually not transparent
2 w& q* f9 j1 z9 O4 y2 i) J
( n6 [% H6 ? [3 K9 x" Y, \3 \( sCrystal structures (1)
6 K2 e: A0 R- O; z/ K7 d& d+ a( J
8 X7 G1 {! {1 s [2 s
" g( A0 v, U" o4 ^3 F p2 X
; T4 p% M# S/ I% h3 d7 C
Crystal structures: the unit cell (2)
- H! i* I: ~$ _1 ]7 l# Q1 S% p' y3 u( n% ]/ e7 g' x# x
8 P: k3 k" w) C4 Q$ I! p! K% E
8 e" G m6 E% x" q8 nMacro structure: the spherulite (1)
- {; o9 g% l# h
! n8 V& y. ^/ H `/ K- D2 i2 JMost of the semi-crystalline resins crystallize into a spherulitic macro structure. The macromolecules loop on themselves to shape a lamella. The lamellas are assembled into a spherical super structure called spherulite. The spherulite is growing from a center point, the nucleation point.
( J, c/ @# W' |2 ^2 s% T# `) ?; j# |+ K# e: ~
; b) |' A& V2 R2 n6 `+ U. n
. k2 o& w$ ?( a7 U
Macro structure: the spherulite (2)
4 e* `/ N2 ]. t) L2 q, D
' i! d/ U- X+ E0 m! \% sThe crystalline entities can also be discs or rods. Once the crystalline entities growth is blocked up by other crystralline entities, the primary crystallization is over and start the secondary crystallization between crystalline entities or lamellas.
2 Y$ V9 k% ^# K0 R, s
Macro structure
& m2 k7 V; F) R5 }) X- |3 p. O! \% J+ x s
Crystalline resin
9 z* y4 _8 J. q. z) h3 E6 ]+ J) n
: _' v- L% J, j G3 f
8 C o* B- K0 w! {2 a+ @" i/ ~
( ^& `* f& k' \' u- b( Z5 k
Semi-crystalline resin
. ?+ o; D) M' i% o
! o! }( e2 o6 |3 a/ V$ X# B
' w. W- q. L; s# u5 V3 P: S2 g
" O; M2 O4 C8 R: T8 iSemi-crystalline vs amorphous resin (DSC)
4 `/ P$ \2 E, N
; _2 v- \( _. D
7 n* m; N9 @" Q
+ N n: S' R+ q. F1 hTg and Tm: some examples
6 p6 @) _. r) E( u6 X
* D6 i+ d7 L/ L' a! `* s
0 Y5 T3 ?6 p. Q; _- J& J( ^: | \" ?- R
Typical process temperatures
; O& {5 l- p! w( {) _
+ j& s0 O4 u* S$ H0 Z: { J
7 x8 F1 }; V6 q/ H2 F3 Q7 I( V- k9 l* o5 r8 ?: ~; W6 {% p; t/ c! K
Physical properties
- p* _& v, V1 m. d: C. Z" J P) U& f, S! A
9 B; h$ W% s4 Q8 |( B' c
# |2 i$ ^/ e! x( fThermoplastic families / Applications
8 A. M3 t3 e9 r9 j7 L% H) S
( f8 w2 f, W8 R* W5 r; m
2 w, Q' w) }! `5 v
' G( j: B! ~/ z8 H5 @# h
Thermoplastic families / Applications
, U3 N; t; F/ O
$ \4 y3 b! Q- j4 D) ?
, Y& V# M9 f/ B3 s, }$ g, ?9 F0 R( [( N, Q# G) h0 f
Thermoplastic families / Applications
, Z% O, {& t) K4 G1 }1 u$ c
2 N3 r$ m' W a( H; w, S
% ^/ r C2 F/ p3 p; V4 r
& I0 `# B1 G/ V7 X$ V: w
0 V2 Z3 D1 t% y; j1 e
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