Krtouš Zdeněk, Hanyková Lenka, Krakovský Ivan, Nikitin Daniil, Pleskunov Pavel, Kylián Ondřej, Sedlaříková Jana, Kousal Jaroslav
Faculty of Mathematics and Physics, Charles University, V Holešovickách 2, 180 00 Prague, Czech Republic.
Faculty of Technology, Tomas Bata University in Zlín, Vavrečkova 275, 76001 Zlín, Czech Republic.
Materials (Basel). 2021 Jan 19;14(2):459. doi: 10.3390/ma14020459.
Plasma polymer films typically consist of very short fragments of the precursor molecules. That rather limits the applicability of most plasma polymerisation/plasma-enhanced chemical vapour deposition (PECVD) processes in cases where retention of longer molecular structures is desirable. Plasma-assisted vapour thermal deposition (PAVTD) circumvents this limitation by using a classical bulk polymer as a high molecular weight "precursor". As a model polymer in this study, polylactic acid (PLA) has been used. The resulting PLA-like films were characterised mostly by X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) spectroscopy. The molecular structure of the films was found to be tunable in a broad range: from the structures very similar to bulk PLA polymer to structures that are more typical for films prepared using PECVD. In all cases, PLA-like groups are at least partially preserved. A simplified model of the PAVTD process chemistry was proposed and found to describe well the observed composition of the films. The structure of the PLA-like films demonstrates the ability of plasma-assisted vapour thermal deposition to bridge the typical gap between the classical and plasma polymers.
等离子体聚合物薄膜通常由前驱体分子的非常短的片段组成。在需要保留较长分子结构的情况下，这相当限制了大多数等离子体聚合/等离子体增强化学气相沉积（PECVD）工艺的适用性。等离子体辅助气相热沉积（PAVTD）通过使用经典的本体聚合物作为高分子量“前驱体”来规避这一限制。在本研究中，聚乳酸（PLA）被用作模型聚合物。所得的类聚乳酸薄膜主要通过X射线光电子能谱（XPS）和核磁共振（NMR）光谱进行表征。发现薄膜的分子结构在很宽的范围内是可调的：从与本体聚乳酸聚合物非常相似的结构到使用PECVD制备的薄膜更典型的结构。在所有情况下，类聚乳酸基团至少部分得以保留。提出了PAVTD工艺化学的简化模型，并发现该模型能很好地描述所观察到的薄膜组成。类聚乳酸薄膜的结构证明了等离子体辅助气相热沉积弥合经典聚合物和等离子体聚合物之间典型差距的能力。
