Poly(vinyl alcohol) (PVA) cryogel is a biocompatible, synthetic hydrogel, compatible with magnetic resonance (MR) imaging. It is widely used as a biomaterial in tissue scaffolds and mimics to test various diagnostic techniques. The aim of this study is to characterise the effect of varying PVA concentration, molecular weight (MW) and manufacturing protocol on the viscoelastic mechanical properties and MR T₂ relaxation time. Further to this MR imaging (MRI) was investigated as a method to quantify material homogeneity. Cylindrical samples of PVA, of varying MW, concentration and number of freeze thaw cycles (FTCs), were manufactured. Dynamic mechanical analysis was performed to evaluate the storage and loss moduli between frequencies of 0.5 and 10 Hz. MR T₂ relaxation maps were imaged using a 7 T MRI instrument. Storage and loss moduli were shown to increase with MW, concentration, or the number of FTCs; with storage modulus ranging from 55 kPa to 912 kPa and loss modulus ranging from 6 kPa to 103 kPa. MR T₂ relaxation time was shown to increase linearly with PVA concentration. The qualitative and quantitative heterogeneity of the PVA sample were identified through MR T₂ relaxation time maps. Excitingly, PVA demonstrated a composition-dependent casual correlation between the viscoelastic mechanical properties and MR T₂ relaxation time. In conclusion, this research thoroughly characterised the viscoelastic mechanical properties of PVA to support its extensive use as a biomaterial, and demonstrated the use of MRI to non-invasively identify sample heterogeneity and to predict the composition-dependent viscoelastic properties of PVA.

聚乙烯醇 (PVA) 冷冻凝胶是一种生物相容性合成水凝胶，与磁共振 (MR) 成像兼容。它被广泛用作组织支架和模拟物中的生物材料，以测试各种诊断技术。本研究的目的是表征不同的 PVA 浓度、分子量 (MW) 和制造协议对粘弹性机械性能和 MR T ₂弛豫时间的影响。进一步研究了 MR 成像 (MRI) 作为量化材料均匀性的方法。制造了具有不同分子量、浓度和冻融循环 (FTC) 次数的 PVA 圆柱形样品。进行动态力学分析以评估 0.5 和 10 Hz 频率之间的存储和损耗模量。先生T ₂松弛图使用 7 T MRI 仪器成像。存储和损失模量随着 MW、浓度或 FTC 数量的增加而增加；储能模量范围为 55 kPa 至 912 kPa，损耗模量范围为 6 kPa 至 103 kPa。MR T ₂弛豫时间显示出随PVA浓度线性增加。PVA 样品的定性和定量异质性通过 MR T ₂弛豫时间图确定。令人兴奋的是，PVA 证明了粘弹性力学性能与 MR T ₂之间存在依赖于成分的偶然相关性休息时间。总之，这项研究彻底表征了 PVA 的粘弹性力学特性，以支持其作为生物材料的广泛应用，并证明了使用 MRI 无创识别样品异质性并预测 PVA 的成分依赖性粘弹性。