TA Instruments User Training
DSC原理與應用
2012年9月7日
國立台灣大學化學系 潘貫講堂 (B棟積學館2樓演講廳)
基礎應用
許炎山
TA Instruments, Waters LLC
美商沃特斯國際股份有限公司台灣分公司
TA Taipei office: 104臺北市長安東路1段23號4F之5
Tel: 02-25638880
C/P: 0928-168676
Fax: 02-25638870
E/M : [email protected]
DSC: Heat Flow Measurements
Calorimeter Signals
Time
Temperature
Heat Flow
Signal Change
Heat Flow, absolute
Heat Flow, shift
Exothermic Peak
Endothermic Peak
Isothermal Onset
Properties Measured
Specific Heat
Glass Transition
Crystallization or Cure
Melting
Oxidative Stability
Heat Flow → exothermic
DSC: Typical DSC Transitions
Oxidation
or
Decomposition
Melting
Glass
Transition
Crystallization
Temperature
Cross-Linking
(Cure)
Endothermic Heat Flow
0 .1
0 .0
Heat Flow (W/g)
-0 .1
ƒ Heat Flow
ƒ Endothermic: heat flows into the sample as a
result of either heat capacity (heating) or
some endothermic process (glass transition,
melting, evaporation, etc.)
-0 .2
-0 .3
-0 .4
0
E xo U p
25
50
75
T e m p e ra tu re ( 蚓 )
100
125
150
Exothermic Heat Flow
Heat Flow (W/g)
0 .1
ƒ Heat Flow
ƒ Exothermic: heat flows out of the sample
as a result of either heat capacity (cooling)
or some exothermic process (crystallization,
cure, oxidation, etc.)
0 .0
-0 .1
0
E xo U p
20
40
60
80
Te m pe ra ture ( 蚓 )
100
120
140
160
Understanding DSC Signals (cont.)
Heat Flow (cont.)
Where:
dH
= measured heat flow rate
dt
Cp = sample heat capacity
= specific heat (J/g°C) x mass (g)
dT
dt = measured heating rate
f (T,t) = heat flow due to kinetic processes
(evaporation, crystallization, etc.)
Understanding DSC Signals (cont.)
Heat Flow Due to Heat Capacity
ƒ Heat Capacity = Specific Heat (J/g°C) x mass (g)
ƒ For a given sample, the higher the heating rate, the higher the heat
flow rate. Therefore, high heating rates increase sensitivity to
detect weak transitions
Heat Flow Rate = mWatt = mJ/sec
ƒ The heat flow rate becomes endothermic as heating of the sample
begins (due to sample Cp at that temperature) and becomes more
endothermic at higher temperature due to increasing sample Cp at
higher temperature During cooling, the heat flow signal is
exothermic
Understanding DSC Signals (cont.)
Heat Flow Due to Heat Capacity (cont.)
ƒ Absolute Heat Capacity or Specific Heat (J/g°C)
is important because:
1.
2.
It is required by engineers to develop systems that heat or
cool materials
It is a measure of molecular mobility
Vibration – occurs below and above Tg
Rotation – polymer backbone and sidechains (in and above
Tg)
Translation – polymer molecule (above Tg)
ƒ
Changes in heat capacity are important
because they signal significant changes in the
physical properties of a material
Heat Flow Due to Heat Capacity
Tg is a Step Change in Heat Capacity
-0.3
2.0
-0.4
1.5
Glass Transition is Detectable by DSC
Because of a Step-Change in Heat Capacity
Heat Capacity
Heat Flow
-0.7
Temperature Below Tg
- lower Cp
- lower Volume
- lower CTE
- higher stiffness
- higher viscosity
- more brittle
- lower enthalpy
1.0
-0.6
[ ––––– · ] Heat Flow (mW)
Heat Capacity (J/g/°C)
-0.5
-0.8
-0.9
0.5
-1.0
70
Exo Up
90
110
Temperature (°C)
Universal V3.8A TA Instruments
Heat Flow Due to Kinetic Events
Applications
ƒThermoplastics
ƒThermosets
ƒPharmaceuticals
ƒHeat Capacity
ƒGlass Transition
ƒMelting and Crystallization
ƒAdditional Applications Examples
Thermoplastic Polymers
Semi-Crystalline or Amorphous
Crystalline Phase
melting temperature Tm
(endothermic peak)
Amorphous Phase
glass transition
temperature (Tg)
(causing ΔCp)
Tg < Tm
Crystallizable polymer can crystallize
on cooling from the melt at Tc
(Tg < Tc < Tm)
DSC of Thermoplastic Polymers
ƒTg
ƒMelting
ƒCrystallization
ƒOxidative Induction Time (OIT)
ƒGeneral Recommendations
ƒ10-15mg in crimped pan
ƒH-C-H @ 10°C/min
Thermoplastic: Heat/Cool/Heat
First Heat
Cooling
250
Second
Heat
0.0
200
-0.2
150
-0.4
100
-0.6
50
-0.8
0
0
20
40
Time (min)
60
80
[
Heat Flow (W/g)
0.2
] Temperature (°C)
300
0.4
Thermoplastic: Heat Flow vs. Temperature for H-C-H
1.5
Quenched PET
1.0
Cool
Heat Flow (W/g)
0.5
Second Heat
0.0
First Heat
-0.5
-1.0
-1.5
20
60
100
140
180
Temperature (°C)
220
260
Calculation of % Crystallinity
ƒ Sample must be pure material, not copolymer or filled
ƒ Must know enthalpy of melting for 100% crystalline
material (ΔHlit)
ƒ You can use a standard ΔHlit for relative crystallinity
For standard samples:
% crystallinity = 100* ΔHm / ΔHlit
For samples with cold crystallization:
% crystallinity = 100* (ΔHm - ΔHc)/ ΔHlit
PET – Initial Crystallinity
1.0
134.62°C
Heat Flow (W/g)
0.5
0.0
75.43°C
242.91°C
74.71J/g
78.99°C(I)
-0.5
80.62°C
127.72°C
53.39J/g
Initial Crystallinity
-1.0
74.71 − 53.39 = 21.32
256.24°C
-1.5
50
100
150
Temperature (°C)
200
250
300
Crystallinity by DSC
zExample: Crystallinity of
Polyethylene
%Crystallinity =
ΔH obs
f
ΔH
°
f
×100%
Table: Heats of fusion of 100%
crystalline polymers
Q: “Where is my polymer in this table?”
PET Initial Crystallinity Calculation
1.0
134.62°C
Heat Flow (W/g)
0.5
0.0
75.43°C
242.91°C
74.71J/g
78.99°C(I)
-0.5
80.62°C
127.72°C
53.39J/g
% crystallinity = 100* (ΔHm - ΔHc)/ ΔHlit
-1.0
(
74.71 − 53.39 )
100 ×
= 15%
-1.5
50
140
100
150
Temperature (°C)
256.24°C
200
250
300
PET % Crystallinity
ƒ21J/g Initial Crystallinity or 15% Crystalline
ƒDoes that sound right?
ƒThe sample is quenched cooled PET
ƒWe know that quenched cooled PET is 100%
amorphous
ƒWhy does DSC give us the wrong answer?
Change in Crystallinity While Heating
Heat Flow (W/g)
0.5
60
0.0
40
20
-0.5
Integral (J/g)
Quenched PET
9.56mg
10°C/min
1.0
134.63蚓
230.06蚓
71.96J/g
105.00蚓
275.00蚓
127.68蚓
0.6877J/g
230.06蚓
0
-1.0
-1.5
-50
Exo Up
0
50
100
150
Temperature (蚓 )
200
250
300
350
Universal V4.0B TA Instruments
Crystallization
ƒ Crystallization is a kinetic process which can be
studied either while cooling or isothermally
ƒ Differences in crystallization temperature or time (at a
specific temperature) between samples can affect enduse properties as well as processing conditions
ƒ Isothermal crystallization is the most sensitive way to
identify differences in crystallization rates
Crystalline Structures
Single Crystals
Sharmistha Datta & David J. W. Grant, Nature Reviews Drug Discovery 3, 4257 (January 2004)
Polymer Spherulites
Physical State Transitions
Increasing Temperature Î
Amorphous Polymer
Tg
Crystalline Polymer
Liquid
Liquid
Tm
Flexible
Thermoplastic
Gum
Rubber
Tg
Glass
Crystalline Structures
Spherulite Morphology
Folding and “Re-entry”
Youyong Li and William A. Goddard III
Macromolecules 2002 35 (22), 8440-8455
(from Odian)
Effect of Cooling Rate on Crystallization
當結晶速率太快，或是結晶熱太高時的回溫現象
250
Supercooling of Water
-4.36°C
+
Heat Flow (mW)
200
150
100
50
+
0
-15.55°C
-50
-30
-25
-20
-15
-10
-5
Temperature (°C)
0
5
10
Crystallization
• Crystallization is a two step process:
¾Nucleation
¾Growth
The onset temperature is the nucleation (Tn)
The peak maximum is the crystallization temperature (Tc)
•Crystallization is
Temperature and
Time dependence
Effect of Nucleating Agents
2.0
crystallization
POLYPROPYLENE
WITH NUCLEATING
AGENTS
0.0
1.0
Heat Flow (W/g)
Heat Flow (W/g)
1.5
POLYPROPYLENE
WITHOUT
NUCLEATING AGENTS
-0.5
-1.0
melting
0.5
-1.5
60
80
Exo Up
0.0
Exo Up
40
50
100
120
140
160
180
200
Temperature ( 蚓 )
60
70
80
90
100
110
Temperature ( 蚓 )
120
130
140
150
160
What is Isothermal Hot Crystallization?
• A Time-To-Event Experiment
Annealing Temperature
Melt Temperature
Isothermal Crystallization
Temperature
Zero Time
Time
Isothermal Crystallization
5
Polypropylene
117.4 oC
Heat Flow (mW)
4
117.8 oC
3
118.3 oC
2
118.8 oC
119.3 oC
119.8 oC
1
120.3 oC
0
-1
1
3
5
Time (min)
7
9
降溫速率夠快嗎?
Project RHC: Crystallization of LDPE
What is Isothermal Cold Crystallization?
• A Time-To-Event Experiment
Annealing Temperature
Isothermal
Crystallization
Temperature
Melt Temperature
Glass Transition Temperature
Stand-by Temperature
Zero Time
Time
DSC Applications:
Quench-Isothermal-Cold Crystallization
Method Log:
1: Initial temperature: 高於Tm
2: Initial temperature: Tm與Tg之間
3: Mark end of cycle 1
4: Isothermal 恆溫結晶一段時間
5: Mark end of cycle 2
6: Ramp 10.00C/min to高於Tm
7: Mark end of cycle 3
DSC Applications: Quench-Isothermal-Cold
Crystallization of PET
Isothermal
Ramp 10C/min
以MDSC決定樣品的初始結構
Modulated DSC®
Theory & Applications
Advanced Tzero™ technology included in the Q2000, makes MDSC
experiments both faster and the results more accurate. Heating rates equivalent
to those commonly used in standard DSC (10°C / min) are now possible. Over
90% of the leading researchers performing MDSC, use systems from TA
Instruments - a point to note when choosing a DSC system. * US Patent Nos. B1
5,224,775; 5,248,199; 5,335,993; 5,346,306; 5,439,291
DSC Heat Flow
dH
= DSC heat flow signal
dt
Cp = Sample Heat Capacity
= Sample Specific Heat x Sample Weight
dT
dH
= Cp
+ f (T, t)
dt
dt
dT
= Heating Rate
dt
f (T, t) = Heat flow that is function of time
at an absolute temperature (kinetic)
Comparison of DSC and MDSC ® Signals
dH
dT
= Cp
+ f (T, t)
dt
dt
DSC
MDSC
COMMENTS
Total Heat
Flow
Modulated
Heat Flow
Signals contain all thermal
events occurring in the sample
Total Heat
Flow
Quantitatively the same in both
techniques at the same average
heating rate
Reversing
Heat Flow
Heat capacity component of
total heat flow
Nonreversing
Heat Flow
Kinetic component of total heat
flow
Heat Capacity
All calculated heat flow signals
are also available in heat
capacity units
Average & Modulated Temperature:
Heat-Iso Conditions
Amplitude
Average Temperature
Modulated (Actual)
Temperature
Period
Average & Modulated Heating Rate:
Heat-Iso Conditions
Period
Note that the rate never decreases below 0ºC/min
MDSC ® Heat-Cool Temperature Modulation
Heating Rate goes below 0ºC/min
Calculation of MDSC ® Signals
ƒ Total Heat Flow
ƒ Equivalent to standard DSC at the same average
heating rate
ƒ Calculated from the average value of the Modulated
Heat Flow
ƒ The average and amplitude values of the Modulated
Heat Flow are calculated continuously (every 0.1
seconds) using Fourier Transform analysis. This
provides much better resolution than would be
obtained from using the actual average and amplitude
values that occur only twice over each modulation
cycle.
MDSC ® Raw Signals
Quenched PET
MDSC .424/40@4
Signals have an “Average” and
an “Amplitude”
Calculation of MDSC ® Total Heat Flow
Quenched PET – 8.99mg
.424/40@4
Calculation of MDSC ® Signals
ƒ Reversing Heat Flow
ƒ Calculated from Reversing Heat Capacity signal
Heat Flow Amp
Rev Cp =
x KCp Rev
Heating Rate Amp
Rev Heat Flow = Rev Cp x Avg Heat Rate
Calculation of Reversing Heat Capacity Signal
Rev Cp =
Heat Flow Amp
x KCp Rev
Heating Rate Amp
MDSC ® Reversing Heat Capacity Signal
Reversing Heat Flow and Heat Capacity
Calculation of MDSC ® Signals
ƒ Nonreversing Heat Flow
ƒ Calculated by subtracting the Reversing Heat Flow signal from the
Total Heat Flow signal
ƒ Total = Reversing + Nonreversing
ƒ Nonreversing = Total – Reversing
dH
dT
= Cp
+ f (T, t)
dt
dt
MDSC ® Heat Flow Signals
dH
dT
= Cp
+ f (T, t)
dt
dt
Total Heat
Flow
•All Transitions
Reversing Heat Non-Reversing
Flow
Heat Flow
•Heat Capacity
•Glass Transition
•Most Melting
•Enthalpy Recovery
•Evaporation
•Crystallization
•Thermoset Cure
•Denaturation
•Decomposition
•Some Melting
Calculated MDSC ® Heat Flow Signals
Quenched PET – 8.99mg
.424/40@4
MDSC ® Applications: True Range of Melting
Estimated Onset of Melting from Standard DSC
MDSC ® Applications: True Range of Melting
Estimated Onset of Melting from Standard DSC
Estimated Onset of Melting from MDSC
The onset of melting is shown to be 65ºC
lower than estimated from Standard DSC
Polymers; DSC of Complex Polymer Blend
Where are the glass
transitions in this
engineering plastic?
Polymers; MDSC of Complex Polymer Blend
Polymers; DSC of PET/PC Mixture
Sample: Quenched PET and PC
Size: 13.6000 mg
Method: DSC@10
Comment: DSC@10; PET13.60/PC 10.40/Al film 0.96mg
-2
File: C:...\Len\Crystallinity\qPET-PCdsc.001
DSC
Standard DSC @ 10°C/min
57% PET; 43% PC
4
30.74J/g
0
170.00°C
215.00°C
Heat Flow (mW)
270.00°C
42.95J/g
-10
-4
270.00°C
120.00°C
-14
-18
-8
13.31J/g
Where is the glass transition of the
100% amorphous polycarbonate?
-12
DSC Heat Flow Analyzed
Two Different Ways
-22
-16
50
Exo Up
[ ––––– · ] Heat Flow (mW)
120.00°C
-6
100
150
Temperature (°C)
200
250
Universal V3.8A TA Instruments
Polymers; MDSC of PET/PC Blend
Sample: Quenched PET and PC
Size: 13.6000 mg
DSC
Method: MDSC .318/40@3
Comment: MDSC 0.318/40@3; PET13.60/PC 10.40/Al film 0.96mg
File: C:\TA\Data\Len\Crystallinity\qPET-PC.002
-2.0
-2.0
Cold Crystallization Peak
Seen Only in Total Signal
-2.2
Total
Heat Flow
Glass Transition
of Polycarbonate
Heat Flow (mW)
-2.4
-2.4
True Onset
of Melting
-2.6
-2.6
Reversing
Heat Flow
-2.8
-2.8
Decrease in Heat Capacity
Due to Cold Crystallization
-3.0
-3.0
-3.2
-3.2
50
Exo Up
[ ––––– · ] Rev Heat Flow (mW)
-2.2
100
150
Temperature (°C)
200
250
Universal V3.8A TA Instruments
Thermosetting Polymers
A+B
C
Thermosetting polymers react (cross-link) irreversibly.
A+B will give out heat (exothermic) when they crosslink (cure). After cooling and reheating C will have only
a glass transition Tg.
GLUE
EPOXY Resin
Time-Temperature-Transformation (TTT) diagram
Phase Transformations – (Gel and Vitrification)
EPOXY Resin Curing 的過程
Gel 凝膠化 / Vitrification 玻璃化
DSC of Thermosetting Polymers
ƒ Tg
ƒ Curing
ƒ Residual Cure
ƒ General Recommendations
ƒ 10-15 mg in crimped pan if solid; hermetic pan if
liquid
ƒ H-C-H @ 10°C/min
如何表徵熱固性樣品 : DSC動態升溫法與恆溫法
The degree of cure is defined as follows:
ΔH t
α=
ΔH R
Thermoset: Comparison of 1st & 2nd Runs
-0.04
Heat Flow (W/g)
-0.08
First
155.93蚓
Tg
Residual Cure
-0.12
-0.16
Second
Tg
102.64蚓
20.38J/g
-0.20
-0.24
0
50
100
150
200
Temperature (蚓 )
250
300
Determination of % Cure
2.0
DSC Conditions:
Heating Rate = 10 蚓 /min.
Temperature Range = -50 蚓 to 250 蚓
N2 Purge = 50mL/min.
1.5
Heat Flow (W/g)
145.4J/g
54.55 % cured
1.0
Under-cured Sample
-12.61 蚓 (H)
0.5
79.33J/g
75.21 % cured
-5.27 蚓 (H)
0.0
Optimally-cured Sample
NOTE: Curves rescaled and shifted for readability
-0.5
-50
Exo Up
0
50
100
Temperature (蚓 )
150
200
250
Universal V2.4F TA
Effect of Aging/Storage below Tg
物理老化的影響
Physical property
Specific Volume
Modulus
Coefficient of
thermal expansion
Specific Heat
Enthalpy
Entropy
Enthalpic
Relaxation
Response on storage
below Tg
V,
1/E,
Decreases
CTE
Increases
Cp
Decreases
Decreases
Decreases
Decreases
Increases
H
S
Storage
time
Temperature
物理老化對於DSC熱流在Tg範圍產生的影響
Determination of Tg/Cure Factor (Delta Tg)
Î發生錯誤的判斷
(Xiangxu Chen, Shanjun Li,1990)
剖析 ΔTg 的爭議
革新DSC實驗手法的結果
預熱法可以釐清 ΔTg 的爭議
MDSC® Glass Transition of Epoxy Coating
TOTAL
REVERSING
MDSC® Glass Transition of Solder Mask
MDSC ® Applications: Separating Overlapping
Transitions in Epoxy Prepreg
Enthalpy recovery peak
due to physical aging
Glass Transition of Epoxy
MDSC ® Applications: Separating Overlapping
Transitions in Epoxy Prepreg
Tg is over 3ºC higher in
aged sample
Aged Epoxy
Cycled Epoxy (physical aging removed)
MDSC® of Thermoset Cure While Heating
2.0
1.8
1.5
Decrease in Cp Due
to Crosslinking (Vitrification)
Heat Flow (mW)
Reversing
Heat Capacity
1.6
Increase in Cp Due
to Linear Polymerization
1.0
Increase in Cp Due
to Devitrification
1.4
0.5
[ ––––– · ] Rev Cp (J/g/°C)
Sample: Epoxy
Size: 9.79 mg
Method: MDSC at 0.5°C/min
Total Heat Flow
1.2
0.0
103.62°C
319.8J/g
-0.5
50
Exo Up
100
150
Temperature (°C)
1.0
200
Universal V3.8A TA Instruments
Epoxy Cure with Isothermal MDSC®
1.5
Cure Exotherm @ 100°C
1.0
Heating
@ 3 °C/min
256.4J/g
0.5
Heat Flow (mW)
Sample: Epoxy
Size: 10.85 mg
Method: MDSC Iso at 100°C
0.0
75.30min
Residual Cure
-0.5
Decrease in Cp Due to Crosslinking
(Kinetics become Diffusion Controlled)
[ –– –– – ] Temperature (°C)
50.73min
2.4
300
2.2
250
2.0
200
1.8
150
1.6
100
1.4
Iso @ 100°C for 160 min
-1.0
31.06J/g
Temperature
-1.5
1.2
0
Exo Up
350
[ ––––– · ] Rev Cp (J/g/°C)
2.6
50
100
150
Time (min)
200
250
Universal V3.8A TA Instruments
Polymers; Advantage of MDSC for Post
Cure Analysis of Epoxy Resin
0.2
0.4
Heating Experiment at 3°C/min
Heating
Experiment
at 3°
after 160min
Isothermal Cure
@ 100°C
C/min
After 160 min Isothermal
Cure at 100° C
Note inability to see
Tg in Total (like
Note Inability
to
DSC)
signal
Measure Tg
Nonreversing
-0.6
Total
-1.0
Reversing
117.14°C
31.08J/g
110.75°C
0.0
0.0
-0.4
-0.4
-0.8
All Signals at
Same Sensitivity
119.12°C(H)
0.2810J/g/°C
-1.4
-1.2
52
Exo Up
0.4
[ ––––– · ] Rev Heat Flow (mW)
Sample: Epoxy
Size: 10.85 mg
[ –– –– – ] Nonrev Heat Flow (mW)
Heat Flow (mW)
-0.2
Note Onset of Decomosition
before Complete Cure
102
152
Temperature (°C)
202
252
Universal V3.8A TA Instruments
Most Common Applications of MDSC;
Amorphous Structure
ƒ The size (J/g°C) and temperature of the glass
transition provide useful information about the amount
and physical state of amorphous material in a sample.
ƒ The glass transition temperature (Tg) is important
because the sample undergoes a significant change in
physical and reactive properties at this temperature
ƒ Measurement of the glass transition is important to
nearly all DSC users. Because of the significant
change in properties at Tg, it is often difficult to
measure Tg by standard DSC.
Polymers/Drugs; DSC @ 5°C/min for Drug Delivery
System Using Polymer Microspheres
Where are the glass transitions of
amorphous drug dispersed in
amorphous polymer?
Polymers/Drugs; MDSC® @ 2°C/min for Drug
Microspheres Shows Polymer/Drug Miscibility
Single Tg seen in Reversing signal
indicates Drug is soluble in polymer
Drugs; Use of MDSC to Detect Tg in Drug
Formulation
Drugs; MDSC of a Cold/Allergy Tablet
Indicates Decomposition, Not Melting
Lack of endothermic peak in
the Reversing signal indicates
the sample is decomposing
and not melting
Drugs; TGA Analysis of Cold/Allergy Tablet
Shows Decomposition Between 100 and 150ºC
Selecting MDSC® Experimental Conditions (Pan Type)
Pan Type
•
Always do TGA experiment to determine volatile
content and decomposition temperature
○
○
○
•
Volatilization can hide other transitions
Volatilization can affect sample properties or even
structure
Select pan type (crimped vs. hermetic) based on
volatile content and desire to lose or retain volatiles
In general, select thinnest, lightest pan possible
for the sample/application
○
Thin, light pans provide better heat transfer and will
permit shorter modulation periods and faster average
heating rates
TGA Data Shows 5% Weight Loss in Drug Monohydrate
It Does Matter What Pan you use
Monohydrate
Pharmaceutical
sample
MDSC Shows Increase in Cp During Loss of Water Due
to Dehydration of Crystalline Hydrate
Non-Hermetic Pan
Drugs; MDSC Provides Sensitive and Accurate
Measurement of Cp for Casein Protein
20.0°C
1.33J/(g°C)
Drugs; MDSC of Albumin Protein Shows Broad Glass
Transition and an Endothermic Process at Tg on 1st Heat
Drugs; MDSC of Albumin Protein Shows Shows
Just a Broad Glass Transition on 2nd Heat
Drugs; MDSC® Provides an Accurate
Measurement of Tg’ for Freeze-Drying
Enthalpy Plots Are Integrals of Heat Capacity Plots
Integrals of 100% Crystalline and 100% Amorphous Heat Capacity Curves
Can Be Used to Create an Enthalpy Plot
Figure 1
Drug 3.75mg
MDSC® .159/60/1
Figure 2
Effect of the Temperature-Dependence of the Heat of Fusion on Crystallization and Melting
Peak Areas for a Drug
The Enthalpy Plot Can Be Used to Calculate %
Crystallinity
Illustrating the Temperature Dependence of the Heat of
Fusion on the Monohydrate Form of the Drug
Figure 3
Figure 4; % Crystallinity of PET @160 °C
Use of ATHAS Databank to Calculate % Crystallinity on 12.64mg
Sample of Quench Cooled PET after Cold Crystallization
20°C/min