Premium
Acetylene coating on cornstarch plastics produced by cold plasma technology
Author(s) -
Bastos Daniele Cruz,
dos Santos Anastácia Evangelina Fonseca,
Simao Renata Antoun
Publication year - 2014
Publication title -
starch ‐ stärke
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.62
H-Index - 82
eISSN - 1521-379X
pISSN - 0038-9056
DOI - 10.1002/star.201200219
Subject(s) - contact angle , acetylene , raman spectroscopy , coating , thermoplastic , analytical chemistry (journal) , sulfur hexafluoride , materials science , plasma , surface modification , starch , chemistry , composite material , chromatography , organic chemistry , physics , quantum mechanics , optics
This study tested the effectiveness of sulfur hexafluoride (SF 6 ) plasma treatment and acetylene (C 2 H 2 ) plasma polymerization for turning thermoplastic starch (TPS) hydrophobic. A surface modification method was employed using different precursor gases, SF 6 and C 2 H 2 , and a combined treatment using SF 6 followed by C 2 H 2 (SF 6 /C 2 H 2 ) and then the reverse, using C 2 H 2 first followed by SF 6 (C 2 H 2 /SF 6 ). The same self‐bias voltage and treatment time was used for each gas across all treatments: −100 V and 480 s for SF 6 , −200 V and 2400 s for C 2 H 2 . The best results were obtained from a C 2 H 2 ‐coated surface, treated with SF 6 (C 2 H 2 /SF 6 ). This process increased the contact angle to >128°. When treated in the opposite order (SF 6 /C 2 H 2 ), the contact angle decreased to 90° and a homogeneous, smoother coating was produced. Raman spectroscopy confirmed the presence of D and G bands in plasma‐treated films. Under these treatments, all surfaces presented a contact angle higher than 75°.