如今研究人员创造的胶囊是通过把氰基丙烯酸正丁酯和有愈合功效的化合物悬浮其中的油类混合而制的。氰基丙烯酸正丁酯是在超强力胶中发现的一种化学物质。这种混合物再跟稀释的盐酸混合,结果会产生一种乳状液, 其微滴直径在100到300纳米之间。每个微滴都有一颗油核,周围包裹着一层薄薄的氰基丙烯酸正丁酯。为了稳定这些微滴,研究人员在胶状液中添加了磷酸盐,这就促使氰基丙烯酸正丁酯进行聚合反应转变成一种坚固的塑料。这种塑料就形成了胶囊的外壳。
The greatest challenge for the team, however, was not making the capsules in the first place,but stabilising them during the plating process. Though galvanisation is often done by dippingsteel in liquid zinc, it is sometimes done by electrolysisnickel and copper plating are normallydone this way. The capsules, though, tend to stick together in the liquids used as electrolytesduring electroplating, and are also destroyed by the extreme acidity or alkalinity that is ofteninvolved in the process. To overcome these problems, Dr dos Santos and Dr Mayer usedspecial detergents that stick to the polymerised butylcyanoacrylate shell around each capsule,which stops them sticking together and protects them from the electrolytes.
然而,对于这组研究人员来说,最大的挑战并不是开始时胶囊的制造过程,而是在电解过程中如何稳定这些胶囊。尽管一般是通过液态锌蘸洗钢铁来镀锌,有时候也会用电解的方法,在电镀镍和铜时就通常使用电镀。在电镀过程中,不过,胶囊容易在使用的电解质液体中黏在一起,而且也会由于这一过程中通常出现的极酸性和极碱性而受到破坏。为了克服这些问题, dos Santos博士 和Mayer博士使用了一种特殊的去污剂,这种去污剂可以粘附在每个胶囊周围聚合氰基丙烯酸正丁酯的外壳上,阻止这些胶囊黏在一起,并保护它们免受电解液的破坏。
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