Preparation And Properties Of Dressing Made By Hydroxyethyl Cellulose

Hydroxyethyl cellulose, as the important non-ionic cellulose ether, was extensively applied in various fields of textile, daily chemical product, coat, oil, medicine and so on. Hydroxyethyl cellulose, which was a new kind of water-soluble and absorption biomedical hemostatic materials, was non-ionic polysaccharide hydroxyethyl cellulose that could be manufactured through alkalization and etherification by natural polymer fibers, which made the hydroxyl (-OH) of natural fiber replaced by well-soluble hydroxyethyl hydrophilic group [-(OCH2CH2)nOH]. Hydroxyethyl cellulose which could be modified by surface-activeagent had good water-solubility and drug loading capability for excellent nonionic. Hydroxyethyl cellulose without acidic or basic group and no-neurotoxicity, could degrade into monosaccharide in vivo which could be completely absorbed after7to14days by human body.In this paper, the main research contents as follows:(1) Hydroxyethyl cellulose/sodium alginate (HEC/SA) composite sponge was prepared by freeze-drying. The influence of freezing techniques on the sponge molding was studied; and water absorption, water retention and porosity of the sponge were measured; and the structure and performance of sponges were characterized by SEM, FI-IR, TGA and universal testing machine. The result showed that chemical reaction was not happen between Hydroxyethyl cellulose and sodium alginate, and only physical mixing did. HEC/SA composite sponge had poor mechanical properties, good thermal stability, porous structure, good water absorption and water-retention and higher porosity.(2) Two methods were used to modify HEC/SA composite sponge. Hydroxyethyl cellulose and sodium alginate were crosslinked with phosphpric acid; another was that HEC/CA composite sponge was prepared by ion-exchange between Ca2+and Na+. Then the molecular structure of the modified composite sponge was measured by FI-IR; and water absorption, water retention, porosity, mechanical and thermal properties were tested. Results showed the hydroxyl groups in phosphpric, could react with the acetate group of SA and hydroxyl group of HEC resulting in the formation of a covalent bond. Its performance reduced because of the formation of the covalent bond and decrease of hydrogen bond and hydrophilic groups. HEC/CA composite sponge had ion-exchange between Ca2+and Na+, without the formation of covalent bond between the molecular. So its performance was increased due to the introduction of Ca2+.(3) Study the normal saline resistance, biodegradation in vitro and cell biocompatibility of the HEC/SA composite sponge, especially HEC/SA composite sponge crosslinked with phosohate acid. Results showed that HEC/SA composite sponge had good normal saline resistance and stability. But its biodegradation rate was slow, and had good cell compatibility in initial. Cells were killed as degradation. HEC/SA composite sponge crosslinked phosphate was not recommended for wound-dressing.In this article, hydroxyethyl cellulose/sodium alginate(SA) composite sponge was prepared by freeze-drying. Meanwhile two methods were proposed and used to modify HEC/SA composite sponge. Water absorption, water-retention and biocompatibility were investigated on the hemostatic dressing area. This study demonstrated potential medical applications for Hydroxyethyl cellulose as hydrophobic wound-healing and hemostatic materials.