The primary goal of this study is to highlight the rheological and mechanical properties of a new blend composed of naturally-derived hydrogel materials- psyllium husk (PH) and gelatin (G) for its potential use in three-dimensional (3D) printing technology. The mixtures were prepared at various weight ratios of 100PH, 75PH + 25G and 50PH + 50G. A suitable selection of the printable ink was made based on the preliminary screening steps of manual filament drop test and layer stacking by 3D printing. Printing of the common features such as hexagon and square grids helped evaluating shape fidelity of the chosen ink. Although 50PH + 50G blend was found meeting most of the criteria for an ideal 3D printable ink, rheological and mechanical characterizations have been performed for all the ratios of polymeric blends. This study documents the correlation between various factors of rheology that should be taken into account while categorizing any biomaterial as a printable ink. Yield stress was measured as 18.59 ± 4.21 Pa, 268.74 ± 13.56 Pa and 109.16 ± 9.85 Pa for 50PH + 50G, 75PH + 25G and 100PH, respectively. Similarly, consistency index (K) and flow index (n) were calculated using the power law equation and found as 49.303 ± 4.17, 530.59 ± 10.92, 291.82 ± 10.53 and 0.275 ± 0.04, 0.05 ± 0.005, 0.284 ± 0.04 for 50PH + 50G, 75PH + 25G and 100PH, respectively. The loss modulus (G″) was observed dominating over storage modulus (G′) for 50PH + 50G, that depicts its liquid-like property; whereas storage modulus (G′) was found dominating in case of 75PH + 25G and 100PH, indicating their solid-like characteristics. In addition, the loss tangent value (tan δ) of 50PH + 50G was observed exceeding unity (1.05), supporting its plastic behavior, unlike 75PH + 25G (0.5) and 100PH (0.33) whose loss tangent values were estimated less than unity revealing their elastic behavior. Also, 50PH + 50G was found to have the highest mechanical strength amongst the three blends with a Young’s modulus of 9.170 ± 0.0881 kPa.

本研究的主要目的是突出一种由天然水凝胶材料 - 洋车前子壳 (PH) 和明胶 (G) 组成的新型混合物的流变学和机械性能，以使其在三维 (3D) 打印技术中的潜在用途。以100PH、75PH+25G和50PH+50G的不同重量比制备混合物。基于手动丝滴测试和3D打印层堆叠的初步筛选步骤，选择了合适的可打印墨水。六边形和方形网格等常见特征的印刷有助于评估所选墨水的形状保真度。尽管发现 50PH + 50G 共混物满足理想 3D 可打印墨水的大部分标准，但已对所有比例的聚合物共混物进行了流变和机械表征。本研究记录了在将任何生物材料归类为可印刷油墨时应考虑的各种流变学因素之间的相关性。对于 50PH + 50G、75PH + 25G 和 100PH，屈服应力分别测量为 18.59 ± 4.21 Pa、268.74 ± 13.56 Pa 和 109.16 ± 9.85 Pa。同样，一致性指数 (K) 和流动指数 (n) 使用幂律方程计算，发现 50PH + 50G 分别为 49.303 ± 4.17、530.59 ± 10.92、291.82 ± 10.53 和 0.275 ± 0.04、0.05 ± 0.005、0.284 ± 0.04 , 75PH + 25G 和 100PH, 分别。对于 50PH + 50G，观察到损耗模量 (G″) 优于储能模量 (G′)，这描述了其液体状特性；而在 75PH + 25G 和 100PH 的情况下，发现储能模量（G'）占主导地位，表明它们具有类似固体的特性。此外，观察到 50PH + 50G 的损耗角正切值 (tan δ) 超过单位 (1.05)，支持其塑性行为，不像 75PH + 25G (0.5) 和 100PH (0.33)，其损耗角正切值估计小于单位揭示其弹性行为. 此外，发现 50PH + 50G 在三种共混物中具有最高的机械强度，杨氏模量为 9.170 ± 0.0881 kPa。