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几乎所有的商品磁带,都是用聚酯型聚氨酯弹性体作为磁层氧化物的粘合剂和磁带背层粘合剂而制备的。就正常磁带在使用和贮存中,当遇到温度变化时,普通类的聚酯型聚氨酯对环境敏感易产生水解,(即这些材料和大气水汽之间的化学反应)严重的水解可能产生粘连和胶粘化学产物。可以预期,环境所引起的磁带老化和对性能的基本影响起源于酯的水解,环境使商品磁带产生的老化可以通过实验来研究,并且可以发现磁带老化和降解的主要机理是由它的聚酯型聚氨酯粘合剂的水解引起的,这个化学反应是可逆的,这种性质可用于恢复被环境降解了的磁带。作为一个可逆的反应,对于磁带长期存放其理想的相对湿度和温度是室温和相对湿度(RH)24％。本研究对于各种各样的考核试验(工业和行政的规范),可能具有重要性,这些考核试验涉及到磁带的开发或磁带应用的极限湿度和温度。由本工作的发现可以提出,这些试验可以估测和监视水解作用的各种现象,这些现象说明磁带在适当的条件下或在密闭环境中的应用几乎没有什么关系。本工作的结果进一步指出当磁带被密闭隔离空气时比在空气可以更高的温度,它有一个由润滑剂蒸出或聚合物的降解(热解)作用所确定的温度上限。
Almost all commercial tapes are made with polyester polyurethane elastomers as binders for magnetic layer oxides and tape backbones. In normal use and storage of tapes, ordinary polyester polyurethanes are susceptible to environmental degradation when subjected to temperature changes (ie, chemical reactions between these materials and atmospheric water vapor). Severe hydrolysis may cause adhesions and Adhesive chemical products. It is expected that environment-induced tape aging and its basic effect on performance originate from the hydrolysis of esters. The environment allows the aging of commercial tapes to be studied experimentally and the primary mechanism of tape aging and degradation can be found from its polyester Type urethane adhesive caused by the hydrolysis, the chemical reaction is reversible, this property can be used to restore the environment has been degraded tape. As a reversible reaction, its ideal relative humidity and temperature for long-term storage of tape are 24% room temperature and relative humidity (RH). This study may be of importance for a wide range of assessment tests (industrial and administrative norms) that relate to the extreme humidity and temperature of tape development or tape applications. From the findings of this work it can be suggested that these tests allow for the estimation and monitoring of various phenomena of hydrolysis which have little to do with the application of the tape under appropriate conditions or in a confined environment. The results of this work further indicate that when the tape is hermetically insulated from air at a temperature that is higher than air, it has an upper temperature limit determined by the effect of the lubricant being distilled off or the polymer degrading (pyrolyzing).