Complex parts in one operation
+ o( K) Z+ S: I3 [: J; }Wide range of properties
& o3 ?, f$ j* f" ~3 D( `Coloring
; r% i- P0 ]$ e9 X) h- h/ xLow energy requirements
/ B* k: B( B+ v" d) X/ ?) [
Good insulators
9 h3 a9 M% V% G/ f0 M8 V" tLow cost & weight
! F* X: Y# \/ _1 w6 Q O3 i: M; w
Resistance to chemicals
1 ~- l" X1 f9 q9 m: [% P8 X
From monomers to polymers
9 p) P2 q* e: [
Examples : (in between   : monomer )
/ z9 F3 @& d( Q% v8 ZPolyethylene: (catalytic polymerization of ethylene gas under high pressure)
: E3 ~2 o$ I2 }8 h |5 h; X —CH2 — CH2-- CH2 — CH2 -- CH2 —
8 T6 C/ c$ b! B5 i8 N% J1 \$ }1 mPolypropylene: (catalytic polymerization of propylene gas under pressure)
4 f. O6 i: s' T —CH2 — CH-- CH2 — CH -- CH2 —
2 {0 c2 l1 o- ]& Y9 V0 E
CH3 CH3
, {6 V8 { l. b$ H/ d+ u; g
Polyvinylchloride :
; o8 h5 }2 R# l; b0 ? — CH2 — CHCl -- CH2 — CHCl -- CH2 — CHCl —
5 |' ?9 A p" z7 o; i8 _
$ D9 A' m! N/ U3 o" w4 HMolecular weight
0 L$ M7 k* x( K+ Z9 @( ^3 A& D1 i: [2 L
, a- e$ x3 @( j- t# a3 a! s! Q3 u% ~% }6 B1 V
Polymer structures
0 h- D+ o/ W4 i4 Z) o
Homopolymers (ie PP homo)
: Z" }2 n l0 A5 `# FCopolymers (ABS, SAN)
% |# d$ y! n6 @6 ?; a H
random
Z1 Y4 o) M; ~0 |0 f7 x
regular
* j* N) ?8 d3 e; p8 R3 I4 M/ usequenced
/ z p. R, Y' a& tlinear
7 s/ q* A5 ^2 j9 |+ N9 Egrafted
; S) Q! c' h! X4 ~0 I/ JBlends and alloys
3 T5 f" b! b! M% j9 }8 W% Y6 y$ p) {, l N
Polymer structures
* B! y6 Z" }" A" [1 V( JWhy using Blends and alloys?
8 M3 O3 K1 H( `. U. l v cTo combine properties of different polymers.
! A$ T" n1 x+ F5 M
Examples: what brings each polymer in blends below?
0 n# f, F/ K. E' ^5 H2 `% VABS/PC
7 W& ]8 p: A# m) d0 {! K/ ZPC/PBT
& z' Y3 N$ h# e* ~2 [* OPPO/PS
; D6 I% P+ U$ Y, q- @, HPA/PPO
+ O. U0 b# ], c& A0 q! i: J) v2 f# k- l" Q' @
Polymer structures
q) L, U+ W+ |% g1 r0 b7 l0 G; S# j% O% _$ b& a
Crystalline vs Amorphous resin
% K& C0 Z" C: l8 g C( uAre the resin different?
) y2 v& e( H+ |: a$ W
Are the resin processed the same way?
0 H, \0 H7 F. Q+ y/ e
Can the resin be used in the same applications?
+ r# X, F" q6 b- O2 r1 m( b6 t. u0 X# R0 r8 k) f
Amorphous resin
, ~6 e3 m0 Q! j% {+ T+ M
Non organized structure
% z5 B" w; t) n* H
Broad softening range: 20°C
- d( n; s$ m# o6 ?# R- I
High viscosity usually
6 t* i3 } b) V# X/ D; b
Poor chemical properties in general
! d& d) B V0 s: j& z' y+ ECan be transparent
9 D" B4 [. M# B- `6 O6 m2 @* z/ ]1 G: M( M4 J( D. K
Amorphous resin
9 k+ V' r. u. I: c: v$ c$ r* U
, A7 @! ]$ c( U! w
( i# Z$ z+ ^" d j% N- U7 R2 D
4 v' b+ D& k6 L) q* @Crystalline resin
, u! Y) D4 Z* o2 POrganized structure
5 Y) l5 r/ _& v0 k/ [0 {
6 `1 G/ `- W2 ? F1 R: z) L; T; n' ~" v( d3 f; \
" z& Q( r5 B2 @9 ]- JMelting point: within 5°C
; J. l( v: y& G+ k1 X$ TLow viscosity usually
. i. ^) D. F% R4 {4 U
Good chemical properties in general
% z ]4 b* \) H8 y0 xUsually not transparent
1 j W2 A% U6 E# C) m$ o# \ g' t+ K0 K: |0 d
Crystal structures (1)
h4 A$ O X$ J$ I
/ }, X$ b* Q k. V K+ {3 [
I4 ]+ h5 `0 c$ P& j @; r& ^9 C' u( _
Crystal structures: the unit cell (2)
, {0 A" B& d( ~0 A+ E7 u9 g1 _ ~- c8 R6 j8 Q/ L
3 x( V& I# R: f
" I# y9 o( @( Q' h9 F$ T7 BMacro structure: the spherulite (1)
! {4 \9 U& _" g( F, J% `/ W# R9 d: \
; [7 g, x0 I/ S' v. xMost 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.
5 e+ u5 z( K1 A) q( g0 o0 n7 G5 w! E/ j( H( [8 H
9 X" [8 a! q/ s. X1 d6 Q- h
7 y( ?! G; O/ V l0 A" D EMacro structure: the spherulite (2)
% | a( P! N8 z/ ^0 S
# |& R4 d, R" {2 b/ k4 ^. F4 `* ]
The 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.
4 V, v& S$ y' t9 e1 m. V
Macro structure
" l! @8 r# m& r" w, l
% `1 ~, k5 R: ~# r
Crystalline resin
# ?) p5 \* g' }* S3 H* J. D$ B5 g' Z
2 k% C3 X! Y% [: h& Z- z+ C$ g. y$ \! O
Semi-crystalline resin
: G2 k$ @) O5 T
U* B9 a( y8 S- C. p
* ?4 ^: ` h. P1 D. c
) }! w9 E1 |7 z" PSemi-crystalline vs amorphous resin (DSC)
# y, m; h, f+ J5 B) V4 w4 F& ]" k% x$ D, O. x9 b& x8 U2 F, v# l
/ A0 i! c6 D+ {
5 h, R X7 [& }, a* A* u# kTg and Tm: some examples
+ U. V( L: K0 p8 G3 t, P7 C- Q% n, |" T. L3 A5 A2 c; e
) E- Y+ G; w7 d$ {& Y6 a
: m) z; t6 A* ?' DTypical process temperatures
0 W; n9 B s9 Q0 A- w3 d
9 a! q; y- l9 l. b/ i% Z. I; z
7 i; x$ [3 W+ w
) _# A' p4 s* `Physical properties
! J S9 Z" t/ s0 k
: y" Y$ P5 X8 X- s3 `
7 h' ^: M/ O0 C2 R2 a
' o3 ?% u' G8 x5 B/ ]Thermoplastic families / Applications
9 U u8 t6 |2 G: t+ n! j/ \* Z6 T, r" @
; L: }$ z$ O/ ]; p5 z6 H8 V7 {
3 v4 B) ]* h0 r+ S$ X( X4 R& f, gThermoplastic families / Applications
' W; p- n9 J- G
& | Q# H* J& N9 x' L
+ A. \9 E+ ?8 a0 v
0 [0 S* V* L V8 y" Z3 BThermoplastic families / Applications
* q# Y+ _/ S" l/ l, C( r0 Q
6 y0 ?6 S( g4 A' t. H8 \! m. V
. S' g2 O7 H9 w6 S7 m
o4 g: J& G" r2 x
# X/ s) u4 {- m3 a C+ [5 R
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发表于 2014-7-16 18:41
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