Study On Preparation And Properties Of Self-healing Ultrasonically Tissue-mimicking Material

Ultrasound phantoms can be used for training ultrasound biopsy of medical staff.However,most ultrasound phantoms are expensive and do not have self-healing ability at present.So they are not suitable for repetitive invasive operations.To solve this problem,two types of ultrasonically tissue-mimicking material with self-healing properties were prepared in this subject.First,the self-healing SEBS/EC two-phase interpenetrating cross-linked oil gel was made by SEBS matrix,mineral oil solvent,2-(2-ethoxyethoxy)ethanol compatibilizer,ethyl cellulose(EC)scatter.The self-healing ability of this ultrasonically tissue-mimicking material is based on microcrystalline self-healing,hydrophobic interaction and hydrogen bond cooperation.The self-healing performance,acoustic performance and mechanical performance of the material under different EC oil gel and SEBS oil gel ratios and the self-healing ultrasound image of oil gel under heating were explored in this subject.Second,a reversible urea bond-containing crosslinking agent was prepared from dibutylethylenediamine,hydroxyethyl methacrylate(HEMA),and isophorone diisocyanate(IPDI).This agent was prepared to made the dynamic reversible crosslinking SEBS oil gel,which has self-healing ability from reversible urea bond and microcrystalline self-healing.Then the self-healing performance was evaluated.The main research work includes:(1)The self-healing properties,acoustic properties and mechanical properties of SEBS/EC biphasic gel with different ratios of EC oil gel and SEBS oil gel was explored.The results show that the self-healing performance of biphasic gel is higher than pure SEBS oil gel and the recovery rate is up to 37.5±8.5 kPa.With the increase of EC oil gel content,the acoustic velocity of biphasic gel increases and the stability of acoustic performance decreases.When the EC oil gel content is 1.5-7.5 parts,the biphasic gel strength is closed to the human tissue.Heating can promote the self-healing ability of the biphasic gel.Compared with pure SEBS oil gel,the ultrasound image of SEBS/EC biphasic gel is closer to the human finger.(2)The dynamically cross-linked SEBS oil gel based on reversible urea bond and microcrystalline self-healing was prepared.The results show that the gel has good self-healing properties under heating.After self-healing process,the elongation at break of the oil gel is more than 500%and the recovery rate is 70.5%.