4.4 열분석 - kocw

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4.4
(Thermal analysis)
.

, DDTTAA ((DDiiffffeerreennttiiaall TThheerrmmaall
AAnnaallyyzzeerr)),, DDSSCC ((DDiiffffeerreennttiiaall SSccaannnniinngg CCaalloorriimmeettrryy)),,
TTGGAA ((TThheerrmmooggrraavviimmeettrriicc AAnnaallyyzzeerr)),, TTMMAA ((TThheerrmmoo
mmeecchhaanniiccaall AAnnaallyyzzeerr)) ,
DDMMAA ((DDyynnaammiicc MMeecchhaanniiccaall AAnnaallyyzzeerr)),,
DDEEAA ((DDiieelleeccttrriicc AAnnaallyyzzeerr)) .
(Sample) (Reference)
0
(dQ/dt) ,
(T) (t) . ,
TT ((DDTTAA)) oorr ddQQ//ddtt ((DDSSCC)) vvss TT
DTA ,
, DSC
.

,
0.5 ~ 10 mg (pan)
cell .
,
.
DTA 0
. , .
Enthalpy.
,
(Glass temperature: Tg), (Crystallization
temp.: Tc), (Melting temp.: Tm)

.
, Tg
.
(b)
.
Tm enthalpy (H)
.
.
HHaa -- HH
HHaa -- HHcc HHcc:: eenntthhaallppyy
enthalpy Polymer handbook
, 2
.
<< >>
y
.

, , ,
.
TMA (Thermal Mechanical Analyzer)
,
,
.

.

, .
(ε) (σ:
) , .
Sensor
Sinusoidal strain

.
(Modulus: E)
(Stoage modulus; E’) (Loss modulus: E”)
,
EE == EE’’ ++ i EE”” i εo δ
(σ) (σ’)
(σ”) .
εε == εεoo ssiinn wwtt,, σσ == σσoo ssiinn wwtt
, σσ’’ == σσoo ccooss dd,, σσ”” == σσoo ssiinn dd
EE == σσoo // εεoo
EE’’ == σσ’’// εεoo == EE ccooss δδ,, EE”” == σσ””// εεoo == EE ssiinn δδ
,
.
, E’, E”, tan δ ,
, . X-
DMA .
Distribution
Tan δ α (transition), (Chain
segment movements) . (Tg)
,
. ( )
(Segment length)
. (Shoulder curve)
.
E” .
Styrene-Butadiene-
Styrene block polymer (SBS elastomer)
α, β, γ .
α , β
,
γ .
ccaassttiinngg ssoollvveenntt:: :: mmeetthhyyll eetthhyyll kkeettoonnee
:: eetthhyyll aacceettaattee
,
, . , ,
(Cap (Conductance) ,

.





:: ,, :: )
(I) (phase angle shieft; θ)
. (IIaa) (IIoo) .
((CCaappaacciittaannccee,, ffaarraaddss)) :: CC == (( IIaa // VV )) •• (( ssiinn θθ // 22 ππff )),, [[ ff :: HHzz ]]
((ccoonndduuccttaannccee,, oohhmmss)) :: 11 // RR == (( IIoo // VV )) •• ccooss θθ
dipole (ε’) , dipole
(ε”) . ,
, IIoo // IIaa == εε”” // εε’’ == ttaann δδ


, ,
.
Polymethylmethacrylate (PMMA) DEA .
α β , 100Hz~100kHz α
, β . 17.7
kcal/mol .
4.5
, , X- ,
.
, ,
,
( ) .
(Density Gradient Column)

.
(A B)

.
,
,
.
, (Glass bead) ,
, . ,
, .
,
.

,
.
(ρρcc)
(ρρaa) , .
ρρcc –– ρρ ggllaassss bbeeaadd
.
GPC (Gel Permeation Chromatography)
Polystyrene Gel (Columns)
, ,
. Mn, Mw
.
, gel
, ,

.

, (, ) (, )
.
2 ml .

p115
GPC ,
GPC
.
UTM (Universal Testing Machine)
, ( ,
, ) , ,
.
Cross-bar ,
.
.
(Stress-Strain curves) .
, ,
,
(Modulus),
(Work; ) .
() ,
. Cu, Ge, Fe, Na, Pb, As, Al, Ni, Cr, Cd, Mn, Mg Na
.
, .
,
.
.
AA .


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