在此研究中，我們發展出一個能以低能耗的方法去製備自生成的瓊脂微凝膠之顆粒緊密填充分散系統，當瓊脂的濃度低於臨界成膠濃度時(0.4 wt%)，且其水溶液冷卻之後，這些瓊脂微凝膠就會從其溶液內自發性地生成，甚至在濃度極低時(0.04 wt%)，依舊可以觀察到，這些自生成的瓊脂微凝膠仍然會在如此稀薄的水溶液中自發性的生成。而那些濃度高於0.08 wt%的顆粒分散系統，其儲存模數皆高於損耗模數(G’>G”)，並表現出類凝膠行為。而自生成瓊脂微凝膠之高度顆粒堵塞分散系統(1 wt%)可以透過離心來製備，且其展現出液態狀固體的行為及快速自修復的能力。基於凝膠化測試(瓶身倒置及落球測試)的結果，可觀察出其機械性質顯著大於藉由強烈攪拌而製備出的液態凝膠(1 wt%)。自生成瓊脂微凝膠之高度顆粒堵塞分散系統可以用來當作3維列印的支撐材料，所有經過紫外線光固化後的墨水，其結構皆與預先設計的形狀相符，沒有任何變形。除此之外，它也能當作一個新穎的分散劑，可以分散微米級大小的顆粒，展現出優秀的支撐能力。

In this work, a facile and low-energy consumption method is developed to obtain packed dispersions of self-forming agar microgels. As the agar concentration is lower than the critical gelation concentration (0.4 wt%), the microgels are spontaneously formed from the solution with the concentration as low as 0.04 wt% upon cooling. The dispersions with the concentration greater than 0.08 wt% exhibit the yield stress and the storage modulus exceeding the loss modulus (G’ > G”), revealing the gel-like behavior. After centrifugation, a highly jammed dispersion of self-forming microgels (1 wt%) can be acquired, and it behaves like a liquid-like solid with the rapidly self-healing ability. On the basis of the gelification tests (inverted tube and falling ball), its mechanical strength is shown to be significantly stronger than fluid gel (1 wt%) fabricated from strong agitation. The highly jammed dispersion can be used as supporting medium for 3D printing. All the UV-cured structures match their designed shapes perfectly without deformation. Moreover, it can be applied to suspend micron-sized particles in water as a novel dispersant, showing the outstanding supporting ability.

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