Optimization of Atmospheric Plasma Treatment Parameters for Hydrophobic Finishing of Silk Using Box Behnken Design

ABSTRACT

Plasma treatment of mulberry silk fabric was carried out in an indigenously developed plasma reactor in the mixture of helium (He) and commercial fluorocarbon gas at atmospheric pressure. Optical emission spectra (OES) showed the appearance of major atomic lines of helium at 705 nm, 666 nm, 654 nm, 585 nm, and 726 nm. When fluorocarbon gas was introduced into the plasma zone along with helium, it got fragmented and showed atomic lines of fluorine (F) at 429 nm, 357 nm, 341 nm, 325 nm, and for –CF₂ at 318 nm. After He-fluorocarbon plasma treatment, hydrophilic silk fabric turned into hydrophobic. Different important plasma process parameters, i.e. treatment time, helium gas flow and fluorocarbon gas flow were optimized using Box Behnken Design using Design Expert 6.0 software. Scanning electron microscope surface morphology exhibits the deposition of fluorocarbon polymer on the fiber surface without blocking the inter-fiber spacing. Hydrophobic characteristic of plasma-treated samples was evaluated by measuring water absorbency time and contact angle value. The sample could retain the imparted hydrophobic finish till 10 repeated washing cycles.

摘要

摘要在自行研制的等离子体反应器中，在常压下用氦气和工业氟碳混合气体对桑蚕丝织物进行了等离子体处理. 在705 nm、666 nm、654 nm、585 nm和726 nm处出现了主要的氦原子谱线. 当氟碳气体与氦一起进入等离子体区时，其发生碎片化，在429 nm、357 nm、341 nm、325 nm处出现氟(F)原子线，在318 nm处出现氟(F)原子线，在-CF2处出现氟(F)原子线. 经氟化碳等离子体处理后，真丝织物由亲水变为疏水. 利用Design Expert 6.0软件，利用盒子Behnken设计软件对不同重要的等离子体工艺参数，即处理时间、氦气流量和氟碳气体流量进行了优化. 扫描电子显微镜表面形貌显示氟碳聚合物沉积在纤维表面，而不堵塞纤维间的间距. 通过测定吸水性时间和接触角值，评价等离子体处理样品的疏水性. 样品经十次重复洗涤后仍能保持原有的疏水性整理.

KEYWORDS:

• Mulberry silk
• hydrophobic
• plasma
• Box Behnken Design
• wash durability

关键词:

• 桑蚕丝
• 疏水
• 等离子体
• 盒子Behnken设计
• 洗耐用性

Acknowledgments

Authors are thankful to Director, ICAR-Central Institute for Research on Cotton Technology, Mumbai for plasma treatment of textile, developed under NFBSFARA project.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.