不同聚合單元體成份對於聚對苯二甲酸丁二酸丁 二酯之物性、機械強度與脂解酶分解性之影響

The physical, mechanical and lipase-degradable properties of poly(butylene succinate-co-terephthalate) of various monomer compositions

蔡秉勳(Ping-Hsun Tsai)

指導教授 ： 陳志成

大同大學/工程學院/生物工程學系所/碩士(2010年)

摘要

本研究以琥珀酸(Succinic acid, SA)、對苯二甲酸二甲酯(dimethyl terephthalate, DMT)及1,4-丁二醇(1,4-butandiol, BDO)等單體藉由轉酯 化反應(transesterification)及聚縮合反應(polycondensation)等步驟合成 聚對苯二甲酸丁二酸丁二酯Poly(butylene succinate-co-terephthalate) (PBST)。本實驗分為三個部份，第一部份以2的3次方實驗設計探討聚縮合溫 度、BDO/DMT比例及SA/DMT比例三個因子對共聚酯本質黏度 (intrinsic viscosity, [η])之關聯性。由統計分析結果顯示，溫度因子較 其他兩個因子對共聚酯之[η]更具有顯著影響，P-value（＜0.05）。並 以Berkowitz公式計算出數目平均分子量（Mn）與[η]的關係式為Mn＝ 1.521×10的5次方×[η]的1.5次方。第二部份於實驗過程中探討聚縮合溫度、催化劑 (tetrabutyl titanate, Ti(Obu)4)濃度及BDO/( SA+DMT)之莫耳百分比對合成PBST之[η]的影響。實驗結果發現，當SA/(SA+DMT)＝50 mol% ，而BDO/(SA+DMT)=1.2 mol/mol ， Ti(Obu) ＝ 0.97 mmol/mol(DMT+SA)及聚縮合溫度於250℃，聚縮合反應時間1.5 小時，PBST之[η]達0.48 dL/g為最佳。第三部份於實驗過程中探討
SA/(SA+DMT)比例之影響。實驗結果發現，熱性質方面，當單體莫耳百分比SA/(SA+DMT)=30 mol%時，共聚酯之熔點為最高，可達177℃。在機械強度方面，共聚酯之最大拉伸強度(Tensile strength)以SA/(SA+DMT)=30 mol%時可達25.6MPa；共聚酯之最大延伸率
(Elongation)以SA/(SA+DMT)=60 mol%時可達269.3%；共聚酯之楊氏模數(Young modulus)以SA/(SA+DMT)=30 mol%時可達754.8MPa。在生物分解性方面，脂解酶最大分解速率以SA/(SA+DMT)=80 mol%比例之共聚酯於6 天時分解率達100%。

關鍵字

生物可分解 ； PBST ； 脂肪族-芳香族聚酯 ； 機械強度

並列摘要

In this study, a series of Poly(butylene succinate-coterephthalate) (PBST)
of various monomer compositions were synthesized from succinic acid
(SA), dimethyl terephthalate (DMT), and 1,4-butanediol (BDO) in the
presence of tetrabutyl titanate (Ti(Obu)4) by transesterification and
polycondensation. The experiment was divided into three parts. The first
part is a 23 factorial design with three factors of temperature, molar ratio
of BDO/DMT, and molar ratio of SA/DMT in polycondensation. Our
statistical analysis showed that the temperature has a more significant
effect on the intrinsic viscosity ([η]) of PBST than the other two factors.
The number-average molecular weight (Mn) of the PBST was determined
from the intrinsic viscosity by using the Berkowitz model of Mn =
1.521×105[η]1.5. The second part of the experiment is a time course
investigation of polycondensation under various temperatures, molar
ratios of BDO/(DMT+SA), and concentrations of Ti(Obu)4. Our results
showed the best polycondensation occurred at 1.5 hr with [η] reaching
0.48 dL/g when the temperature was held at 255 °C, BDO/(DMT+SA) =
1.2 with SA/DMT = 50 mol%, and 0.97 mmol of Ti(Obu)4 per mol of
DMT+SA. The third part of the experiment involves searching for the
best molar ratio of SA/DMT in obtaining desirable polymer properties
and biodegradability. The results showed that the highest melting point of
PBST can be as high as 177 °C at SA/DMT = 30 mol%. The maximum
tensile strength of 25.6 MPa is obtained at SA/DMT = 30 mol%. The
maximum elongation at break of 269.3% and the maximum Young's
modulus of 754.8 MPa are reached at SA/DMT = 60 mol% and at
SA/DMT = 30mol%, respectively. Whereas the fastest
lipase-decomposition rate of PBST reached 100 % at 6 days for samples
with molar ratio SA/DMT = 80 mol%.

並列關鍵字

Biodegradability ； PBST ； Aliphatic-aromatic copolyester ； Tensile properties

參考文獻

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