本實驗研究熔融紡絲聚醯胺-11(Polyamide-11, PA11)與熱塑性聚氨酯(Polyurethane, TPU)和熱塑性聚脲(Polyurea, PUA)，製備成芯鞘型與海島型纖維探討其形狀記憶功效，以PA11此具低吸水率、耐油性好的材料作為包覆層，而熱塑性彈性體作為內層提供形狀記憶效能，熱塑性彈性體主要分為TPU與PUA兩大類，TPU與PUA兩者最大的差別，以化學結構來看在於PUA擁有較多的N-H鍵，可產生較多的氫鍵作用力，使其兩相相容性佳，產生較多的交聯點，有助於形狀記憶效能。
先以熔融共混研究其薄膜形狀記憶功效；本實驗亦藉由溶脹實驗計算出交聯密度，比較TPU與PUA兩系統後發現，PUA系統雖有較高的交聯密度，但在薄膜形狀記憶效能部分，TPU與PUA系統在固定率與回復率部分皆達到90%以上，進而嘗試以熔融紡絲裝置製備PA11/TPU和PA11/PUA複合纖維。
本研究使用雙組份熔融紡絲機搭配芯鞘型與海島型紡嘴，生產出PA11/TPU及PA11/PUA芯鞘型和海島型複合纖維，在熔融紡絲加工中，會給予纖維一定延伸力，可促進分子鏈順向度，因此纖維型態的形狀記憶效能高於薄膜型態，而兩種型態纖維差異處在於海島型纖維中PA11與彈性體接觸面積大於芯鞘型纖維，進而影響其交聯密度，經過三次形狀記憶循環後，PA11/TPU芯鞘型纖維的固定率為 98.5 %，回復率99.6%，PA11/TPU海島型纖維的固定率為99.5%回復率為99.9%，PA11/PUA芯鞘型纖維的固定率為98.4率為99.6 %，PA11/PUA海島型纖維的固定率為98.8 %回復率為99.9 %，先前相關研究大多製備高分子形狀記憶薄膜，本研究成功生產芯鞘型與海島型形狀記憶複合纖維，期望能增加形狀記憶材料應用領域。

Thermoresponsive shape memory fibers were prepared by melt spinning facilities. Polyamide-11 and thermoplastic polyurethane were used to spin into sheath-core and sea-island composite fiber. Polyamide-11, a material with low water absorption and good oil resistance, was used as the outer layer of the fiber. Thermoplastic elastomer was used as the inner layer to provide shape memory performance. Thermoplastic elastomers were mainly divided into two categories: Thermoplastic polyurethane (TPU) and Polyurea (PUA), the mainly difference between two is that PUA system has more N-H bond, which can generate more hydrogen bonding with PA-11 that makes the between phase more compatible, produces more crosslink points which enhance shape memory performance.
Before fiber spinning, shape memory effect in two systems were estimated by hot press melt blending into films. The crosslink density was also calculated by the swelling test. Comparing TPU and PUA system, both systems reached over 90% at either shape memory fix rate and recovery rate, and at the swelling test, PUA system showed a higher crosslink density as predicted. Due to this result, we tried to prepare PA11/TPU and PA11/PUA composite fibers with melt spinning process.
Two-component melt spinning machine with sheath-core and sea-island type nozzle was used to produce composite fiber. In the melt spinning process, during take-up process the as-spun fiber was collected into roll with certain draw ratio, which leads to a better molecularly orientation. In turn improves shape memory effect. After three shape memory cycle, PA11/TPU sheath-core fiber fixation rate is 98.5 %, recovery rate is 99.6 %. PA11/TPU sea-island fiber fixation rate is 99.5%, recovery rate is 99.9%. PA11/PUA sheath-core fiber fixation rate is 98.4 %, recovery rate is 99.6 %. PA11/PUA sea-island fiber fixation rate is 98.8 %, recovery rate is 99.9 %. The research has successfully produced sheath-core fiber and sea-island shape memory composite fiber, and expected to increase the application field of shape memory materials.

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