Competition in Crystallization between Different Components and Formation of Concentric Double Spherulites in Block Copolymers

嵌段共聚物中不同组分之间的结晶竞争与同心双球晶的形成

• 批准号: 09650991
• 负责人: SHIOMI Tomoo
• 金额: $ 2.37万
• 依托单位: Nagaoka University of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650991/
• 关键词: Crystallization; Spherulite; Concentric circles; Block copolymer; Poly (epsilon-caprolactone); Poly (ethylene glycol); Long spacing

A unique morphology of spherulites, namely double spherulites like concentric circles, was observed for poly(epsilon-caprolactone)-block-poly(ethylene glycol)-block-poly(epsilon-caprolactone) (PCL-PEG-PCL) triblock copolymers, ABA-2 and ABA-3, with PCL compositions of 66 and 60 wt%, respectively. The inside and outside spherulites in the concentric spherulites were those of PCL and PEG, respectively. In formation of the conceniric spherulites, the spherulites of the PCL component first occurred necessarily and grew, and then the PEG spherulite developed from the growth front of the PCL spherulite. Any nucleation of the PEG spherulite prior to that of PCL was not observed. In the triblock copolymers, ABA-1 and ABA-4, with PCL compositions of 83 and 34 wt%, respectively, no concentric spherulites were observed but a usual single spherulite was formed ; in ABA-1 only PCL spherulites was formed while only PEG spherulite was observed in ABA-4. Two melting peaks appeared for ABA-2 and ABA-3 in which the concentric spherulites was observed. The SAXS curves also had two kinds of peaks due to alternating structure of the crystal lamella and amorphous layer for both ABA-2 and ABA-3. The long spacing estimated from the peak position suggested that the amorphous chains of the counter component existed between the crystal lamella.

聚（ε-己内酯）-嵌段-聚（乙二醇）-嵌段-聚（ε-己内酯）（PCL-PEG-PCL）三嵌段共聚物ABA具有独特的球晶形态，即同心圆状的双球晶-2 和 ABA-3，PCL 成分分别为 66 和 60 wt%。同心球晶中的内、外球晶分别为PCL和PEG。在同生球晶的形成过程中，PCL组分的球晶首先必然出现并生长，然后从PCL球晶的生长前沿发展出PEG球晶。没有观察到 PEG 球晶先于 PCL 成核。在 PCL 组成分别为 83 和 34 wt% 的三嵌段共聚物 ABA-1 和 ABA-4 中，没有观察到同心球晶，但形成了通常的单个球晶；在ABA-1中仅形成PCL球晶，而在ABA-4中仅观察到PEG球晶。 ABA-2和ABA-3出现两个熔化峰，其中观察到同心球晶。由于 ABA-2 和 ABA-3 的晶层和非晶层的交替结构，SAXS 曲线也有两种峰。从峰位置估计的长间距表明反组分的无定形链存在于晶体片层之间。

项目成果

塩見友雄: "多相高分子の結晶化の特性" 日本ゴム協会誌. 71. 209-216 (1998)

Tomoo Shiomi：“多相聚合物的结晶特性”日本橡胶协会杂志 71. 209-216 (1998)。

塩見 友雄: "多相高分子の結晶化の特性" 日本ゴム協会誌. 71. 209-216 (1998)

Tomoo Shiomi：“多相聚合物的结晶特性”日本橡胶协会杂志 71. 209-216 (1998)。

塩見 友雄: "多相高分子の結晶化の特性" 日本ゴム協会誌. 71・4(予定). (1998)

Tomoo Shiomi：“多相聚合物的结晶特性”日本橡胶协会杂志71・4（预定）。

T.Shiomi, K.Imai, K.Takenaka, H.Hayashi, Y.Tezuka: "Appearance of Double Spherulites like Concentric Circles for Poly (epsilon-caprolactone) -blocsk-Poly (ethyleneglycol) -block-Poly (epsilon-caprolactone)" Macromolecules. in press.

T.Shiomi、K.Imai、K.Takenaka、H.Hayashi、Y.Tezuka：“聚（ε-己内酯）-blocsk-聚（乙二醇）-block-聚（ε-己内酯）的同心圆双球晶外观

塩見友雄: "高分子多相系の結晶化" 繊維学会誌(繊維と工業). 55・3発表予定. (1998)

Tomoo Shiomi：“聚合物多相体系的结晶”日本纤维科学技术学会杂志（纺织工业）预定于3月55日发表。（1998年）。