指導教授 : 王振乾 教授 學生 : 符昌中

• 聚氨酯 (PU) 具有優異的特性，且經由封閉後，可作為羥基化合物的交聯劑；封閉後的 PU 也有較好的儲存性。

• 在解封閉的過程中，會有不必要的氣體 ( 封閉劑 ) 揮發較為不環保，應儘量減少環境汙染。

• 本實驗是藉由不同的封閉劑，降低解封閉的溫度，找出解封閉的反應機制。

Introduction

• Hexamethylenediisocyanate (HDI)

• Isophorondiisocyanate (IPDI)

Materials

Materials

• Isopropanol (IP)

• Bisphenol A (BPA)

• 4-Hydroxybenzoic acid ethyl ester (HBEE)

Isocyanate in acetone(dried and distilled under N2)

four-necked flask

blocking agent (aromatic) in acetone

the pure blocking agent(aliphatic)

After cooling, the solution was precipitated with intense stirring in ice-water.

recrystallized in acetone and again dried in vacuo at 40 .℃

Synthesis

Isocyanate and blocking agent were dried at 50 for 4 h under ℃vacuum.

Isocyanate and blocking agent were dried at 50 for 4 h under ℃vacuum.

The reaction was carried out using an oil bath at a temperature of 100 .℃The reaction was carried out using an oil bath at a temperature of 100 .℃

The end of the reaction was detected by FTIR.The end of the reaction was detected by FTIR.

Synthesis

Comparison of the signals obtained by STA-MS of the system HDI/HBEE: (−) DSC; (- - - -) DTG; (--)56 amu; (--) 121 amu.

It can be seen in the DSC curve that the endothermic reaction due to the deblocking starts directly after the melting (peak maxima of melting at 117 and 133 for HDI/HBEE).℃

It can be seen in the DSC curve that the endothermic reaction due to the deblocking starts directly after the melting (peak maxima of melting at 117 and 133 for HDI/HBEE).℃

Tm

deblocking

Results and discussion

The first deviation in the DTG curve and the first signs of mass numbers were found at about 150 . This value is higher than the value determined by DSC or FTIR because ℃the volatility of the components is not given at the start of deblocking reaction.

The first deviation in the DTG curve and the first signs of mass numbers were found at about 150 . This value is higher than the value determined by DSC or FTIR because ℃the volatility of the components is not given at the start of deblocking reaction.

Results and discussion

Temperature dependent FTIR spectra of the deblocking reaction of the urethane model compound HDI/HBEE in the range between 1850 and 950 cm-1.

δNH (urethan) at 1536 cm-1

C=O (allophanate)at 1690 cm-1

Results and discussionHDI/HBEE

Temperature dependent FTIR spectra of the deblocking reaction of the urethane model compound HDI/HBEE in the range between 2500 and 2100 cm-1.

The new isocyanate absorption band at 2276 cm-1

Two new bands at 2336 and 2369 cm-1

were found.

Results and discussionHDI/HBEE

Integral absorbances of isocyanate and carbon dioxide vibration during the deblocking reaction of the urethane model compound HDI/HBEE studied by FTIR in dependence on time during the non-linear heating:( D )NCO (2303-2200 cm-1); (- - - -) CO2 (2349-2307 cm-1); (-··-··) temperature.

Results and discussion

HDI/HBEE

Temperature dependent FTIR spectra of the deblocking reaction of the urethane model compound HDI/BPA in the range between 2500 cm-1 and 2100 cm-1.

The new isocyanate absorption band at 2276 cm-1

Two new bands at 2336 and 2369 cm-1

were found.

Results and discussionHDI/BPA

Temperature dependent FTIR spectra of the deblocking reaction of the urethane model compound IPDI/IP in the range between 2500 and 2100 cm-1.

The new isocyanate absorption band at 2276 cm-1

Two new bands at 2336 and 2369 cm-1

were found.

Results and discussionIPDI/IP

Integral absorbances of isocyanate and carbon dioxide vibration during the deblocking reaction of the urethane model compound IPDI/IP studied by FTIR in dependence on time: ( D ) NCO (2283±2230 cm-

1); (- - - -) CO2 (2349±2307 cm-1); (-··-··) temperature.

IPDI/IP

Results and discussion

Comparison of the signals obtained by STA-MS of the system IPDI/HBEE: (−) DSC; (- - - -) DTG; (--)56 amu; (--) 121 amu.

The detection of mass number 121 (HBEE) at lower temperatures than of 110 (IPDI) and also the shift of maximum temperature to lower values indicate that this system contains unreacted HBEE resulting from the HBEE excess during synthesis which could not be removed completely after synthesis

The detection of mass number 121 (HBEE) at lower temperatures than of 110 (IPDI) and also the shift of maximum temperature to lower values indicate that this system contains unreacted HBEE resulting from the HBEE excess during synthesis which could not be removed completely after synthesis

Results and discussion

Comparison of DSC curves obtained by STA±MS of HDI and IPDI masked with HBEE and BPA.

Results and discussion

• 經由 FT-IR 和 DSC 所得結果， HDI 解封閉溫度較 IPDI 低。

• 利用 STA/MS 和 FT-IR 所得測試的差異，是受異氰酸鹽和解封閉劑的揮發而影響。

• STA/MS 靈敏度較 FT-IR 及 DSC 高。

Conclusions

封閉型異氰酸酯

• 使用四頸瓶熔融聚合

• 溶入 DMF 中，再以乙醇析出。

MDI-DMP-0629-RE

MDI-DMP-0629-RE

MDI-DMP-0629-RE

MDI-DMP-0629-RE

MDI-DMP-0629-RE-heat

• 以 DMAC 為溶劑， NMA 滴入 DMAC/MDI 在四頸瓶中反應

• 溶入 DMF 中，再以乙醇析出。

MDI-NMA-0705-RE

MDI-NMA-0705-RE

MDI-NMA-0705-RE

• 以 DMAC 為溶劑，在四頸瓶中反應• 先將 NMA 與 DMAC 混合，再加入 MDI

• 溶入 DMF 中，再以乙醇析出。

MDI-NMA-0722-RE

MDI-NMA-0722-RE

MDI-NMA-0722-RE

MDI-NMA-0726-RE

• 以 DMAC 為溶劑，倒入 MDI ，再滴入 NMA ，在四頸瓶中反應

• 溶入 DMF 中，再以乙醇析出。

MDI-NMA-0726-RE

MDI-NMA-0726-RE

MDI-NMA-0726

MDI-NMA-0726

MDI-NMA-0727-RE

• 以 DMAC 為溶劑，倒入 MDI ，再滴入 NMA ，在分離式四頸瓶中反應

• 溶入 DMF 中，再以乙醇析出。

MDI-NMA-0727-RE

MDI-NMA-0727-RE

MDI-NMA-0727

MDI-NMA-0728-RE

• 以 DMAC 為溶劑，倒入 MDI ，再滴入 NMA ，在分離式四頸瓶中反應

• 溶入 DMF 中，再以乙醇析出。

MDI-NMA-0728-RE

MDI-NMA-0728-RE

MDI-NMA-0728