熱分析技術 簡介 (DSC, TGA & DMA)

1. 熱分析技術 簡介 (DSC, TGA & DMA) PerkinElmer Thermal Specialist 康瑜容 Tiffany Kang Tiffany.Kang@perkinelmer.com

2. 常用的熱分析方法 • Differential Scanning Calorimetry (DSC) • Thermogravimetric Analysis (TGA) • Thermomechanical Analysis (TMA) • Dynamic Mechanical Analysis (DMA) Page 2

3. 常用的熱分析方法 Page 3

4. 高分子材料結構 Type Structure Example Type of Polymer Chain Structure Poly(vinyl chloride), Polystyrene Polypropylene Polypropylene Poly(imidazol pyrrolones) Linear Branched short chain Long chain branching Ladder Page 4

5. 高分子材料結構 Type Structure Example Type of Polymer Chain Structure (Continued) Phenol-formaldehyde resins Two crosslinked polymers not bonded to each other Crosslinked epoxy with vinyl polymer Star Network Interpenetrating network (IPN) Page 5

6. Polymers Thermoplastics Thermosets (No chemical change on heating) (Chemical change on heating) Uncured Cured Amorphous Crystalline Polystryene LOW/MEDIUM HIGH Epoxies Rubber Polycarbonate Nylon PPS Polyimides Silicones Polyurethanes PET PP Polyesters Neoprene Polysulfone Acetal HDPE Phenolics Epoxy 高分子材料的分類 Page 6

7. Amorphous vs. Crystalline? Amorphous Thermoplastic Crystalline Polymer Page 7

8. Semi-crystalline polymers contain both amorphous AND crystalline phases Properties dominated by both Tg and Tm Semi-crystalline polymers can exhibit additional crystallization during heating Semi-Crystalline Polymer Semi-Crystalline Polymer Page 8

9. Thermosetting Polymer Page 9

10. Schematic Results in Thermal Analysis Quality of sample process DSC(Ex) TGA TMA DMA -Solid Melting • Crystalline • Semi-crystalline • -Amorphous • -Semi-crystalline • -General • -Liquid • -Unspecific Recrystallization Sublimation Solid-solid transition Glass transition Softening without Tg Post-crosslinking Decomposition Ligand release Evaporation Chemical reactions Determination of % Page 10

11. DSC Technique Differential Scanning Calorimetry

12. Question? • PE分成HDPE, LLDPE及LDPE - 結構有何不同? - 性質有何差異? - 結構和性質有何關聯性? • 結晶的過程為何? • 加工條件對結晶有何影響? • 結晶度對透明度的影響? • 添加劑的影響? • DSC可解決哪些問題? Page 12

13. What is DSC ? • 示差掃瞄熱卡量計 • ( Differential Scanning Calorimeter ) : 將樣品置於特定氣氛之下改變其溫度環境或維持在一固定溫度之中去觀察樣品其能量變化，當樣品發生熔融、蒸發、結晶、相轉變等物理現象，或化學變化時，圖譜中將會出現吸熱或放熱帶，進而可推測樣品之性質。 Page 13

14. Thermal Analysis applications - DSC Diamond DSC • Principle: • Heat flow change vs. temperature • Measures: • Phase transition (Tg, Tm, Tc) and heat • Curing reaction and other chemical reactions Page 14

15. Tm Stress Relief Cold Crystallization DH Heat Flow Degradation Tg Start up Transient Curing Ordering Process Temperature Polymer Transitions Page 15

16. DSC Thermal Curve of PET 吸 熱 放 熱 Page 16

17. DSC for curing studies • Detection of Tg • Onset of cure • Maximum rate of cure (peak maximum) • End of cure • Heat of cure Page 17

18. DSC熱示差掃描分析儀之應用 Page 18

19. DSC的設計方式 熱流式 Heat Flux DSC 熱補償式 Power Compensation DSC • 直接量測DH • 不需複雜數學運算 • 爐體較小 • 量測DT • 由DH = kDT計算DH • 爐體較大 Page 19

20. TGA Technique Thermogravimetric Analyzer

21. Thermal Analysis applications - TGA Pyris 1 TGA • Principle: • Weight change vs. temperature • Measures: • Compositions and wt% • Thermal stability and decomposition temp. Page 21

22. 懸吊式 水平式 上置式 TGA Design Concept Page 22

23. TGA Thermal Curves Page 23

24. TGA 的設計原理 主要元件 • Temperature control device • - Furnace, Thermocouple • Weight measurement device • -Null Balance Detector Torque Motor Sample Tare Weight Page 24

25. 水份含量 溶劑含量 塑化劑含量 高分子添加物含量 裂解溫度 灰份含量 無機添加物含量 氧化導引時間測量 TGA-FTIR/TGA-MS 熱穩定測量 不穩定材質測試 異味材質測試 添加物種類測試 TGA-GC/MS 未知物種類判斷 混合溶劑判斷 TGA熱重分析儀 Page 25

26. TGA for compositional analysis • Molding compound contains epoxy and filler • Epoxy can be burned off and residue is inert reinforced filler • TGA provides accurate and reproducible compositional data on molding compound Page 26

27. TMA/DMA Technique Mechanical Analyzer

28. Thermal Analysis applications – DMA/TMA DMA 8000 • Principle: • Viscoelastic properties vs. temperature (DMA) • Dimensional change vs. temperature (TMA) • Measures: • Glass transition point • Storage, Loss modulus and tan delta • Coefficient of thermal expansion (CTE) Page 29

29. What is DMA ? • DMA (Dynamic Mechanical Analyzer) 動態黏彈機械分析儀 將樣品置於特定環境下，偵測樣品在溫度、力量、或頻率改變下，其機械性質變化的情形，進而判定材料的特性。 Page 30

30. E” E’ 材料的黏彈性質… E’ – Storage Modulus 儲存模數 彈性性質 E”– Loss Modulus 損失模數 黏性性質 tan d = E” / E’ Page 31

31. 什麼時候您需要 DMA … • 黏彈機械性質 ex. 模數(Modulus), 黏度(Viscosity), 阻尼相(tan d) … • 微小的相變化 ex. b,g- transition, Tg以DSC/TMA測量不易者 … • 活化能(ActivationEnergy)計算 • 預測材料使用壽命 ex. Creep Recovery, Time-temp. superposition … • 模擬製程中材料及環境變化 ex. Curing process, controlled humidity, Solvent Immersion … Page 32

32.  = 0 o  o 彈性 o o time o k  = 90 time 黏性 time o o time 材料的黏彈性質… DMA即為利用Sine Wave震盪方式, 測量回應的分析儀 Page 33

33. For purely crystalline materials, no Tg occurs. Tg (6) Tb Taor Tg (5) (4) Tg is related to Molecular mass up to a limiting value. (3) In semicrystalline polymers, a crystal-crystal slip, Ta* occurs. Beta transitions are often related to the toughness. E’/Pa Rubbery Plateau (2) For thermosets, no Tm occurs. Rubbery plateau is related to Me between crosslinks or entanglements. Tll in some amorphous polymers Tm - melting (1) Temperature /K • (6) (5) (4) (3) (2) (1) • local bend side gradual large chain • motions and groups main scale slippage • stretch chain chain Idealized DMA Scan Page 34

34. Frequency effects things too • Transitions shift • Behavior changes More elastic E’  More fluid Frequency Page 35

35. So frequency can act like temperature E’ E’ Frequency Temperature Page 36

36. 材料結構特性 成品特性 Molecular weight MW Distribution Chain Branching Cross linking Entanglements Phases Crystallinity Free Volume Localized motion Relaxation Mechanisms Dimensional Stability Impact properties Long term behavior Environmental resistance Temperature performance Adhesion Tack Peel Material Behavior 製程加工特性 Stress Strain Temperature Heat History Frequency Pressure Heat set DMA 連結... Page 37

37. DMA 是如何運作的? Total Force Force motor Static Force Dynamic Force LVDT f Frequency Storage Modulus Amplitude K Fixtures Hold Sample Position Loss Modulus d Phase Thermocouple Furnace Options from -190 to 600 C Page 38

38. 多樣化的夾具選擇 Options: Single Cantilever Dual Cantilever 3 Point Bending Tension Compression Shear Quartz Shear Material Pocket Page 39

39. Applications Powders like drugs, excipients, foods, natural products, etc. Gels Uncured adhesives Coatings Samples that can’t support their own weight Exclusive Material Pockets Pocket closed & sealed Sample in Pocket Pocket open Page 40

40. DMA mode for mechanical properties change • This plot shows DMA results (E’ and tan delta) for cured substrate • DMA gives the most sensitive measure of Tg • DMA results show that substrate is incompletely cured as 2 split peak was found in tan delta around Tg Page 41

41. DMA most sensitive indicator of cure • This plot shows DMA results on completely cured and slightly under-cured PCB’s • Under-cured PCB exhibits a slight increase in E’ above Tg making the board unacceptable Page 42

42. TMA mode for dimensional change • Plot shows results on TMA expansivity of substrate • 1st heat shows that the board contains built in stresses as a result of processing • Stresses are released at Tg • 2nd heat shows classic TMA Tg free of stress relief effects Page 43

43. 更多熱分析的應用… Page 44

44. 高分子熱性質量測

45. 高分子的 Tg 分析 -- 加熱歷史的差異 Page 46

46. 結晶測試 -- 恆溫結晶 Page 47

47. 交連測試 --升溫交連 Epoxy Resin Endothermic Range: 30 mw Heating Rate: 20 oC/min Weight: 32.76 mg Run 1 62.8 oC D H Heat Flow (mW) 113.3 oC Run 2 40 80 120 160 200 240 280 T (oC) Page 48

48. 交連測試 --恆溫交連 Page 49

49. DSC Tg As Function of Cure DSC Heat Flow Less Cured More Cured Temperature 交連測試 --交連度的影響 Page 50

50. More Cured Decrease in Cure Exotherm As Resin Cure Less Increases Cured Temperature 交連測試 --交連度的影響 DSC Heat Flow Page 51