CAJ | 학술논문

用200 W射频容性耦合氧等离子体处理低密度聚乙烯( LDPE)表面1 min,研究了老化温度及时间对LDPE表面成分、形貌和润湿性的影响.扫描电子显微镜结果表明,等离子体改性LDPE表面出现纳米凸点织构,在60和90℃老化24 h后纳米凸点织构特征基本保持稳定. X射线光电子能谱分析表明,等离子体改性LDPE表面经60℃老化24 h后, C-C含量由76.9%增至83.0%, C-O, C O和O-C O含量分别由16.4%,2.2%和4.5%降至13.1%,1.9%和2.0%.经90℃老化24 h后, C-C含量较60℃老化表面增至84.1%, C-O含量分别降至10.1%, C O和O-C O含量分别增至3.1%和2.7%.等离子体改性LDPE表面接触角由97.2o降至42.3o,经60℃老化24 h后接触角增至95.9o,经90℃老化24 h后接触角增至104.2o,等离子体改性LDPE表面发生“疏水性过回复”.根据含有粗糙因子的接触角随时间演变模型,得到了具有纳米凸点织构LDPE表面在不同老化温度下的可移动极性基团所占面积分数( fpm )、固定极性基团所占面积分数(fpim)和特征时间常数(子)3个成分重构参数,解释了“疏水性过回复”现象.
용200 W사빈용성우합양등리자체처리저밀도취을희( LDPE)표면1 min,연구료노화온도급시간대LDPE표면성분、형모화윤습성적영향.소묘전자현미경결과표명,등리자체개성LDPE표면출현납미철점직구,재60화90℃노화24 h후납미철점직구특정기본보지은정. X사선광전자능보분석표명,등리자체개성LDPE표면경60℃노화24 h후, C-C함량유76.9%증지83.0%, C-O, C O화O-C O함량분별유16.4%,2.2%화4.5%강지13.1%,1.9%화2.0%.경90℃노화24 h후, C-C함량교60℃노화표면증지84.1%, C-O함량분별강지10.1%, C O화O-C O함량분별증지3.1%화2.7%.등리자체개성LDPE표면접촉각유97.2o강지42.3o,경60℃노화24 h후접촉각증지95.9o,경90℃노화24 h후접촉각증지104.2o,등리자체개성LDPE표면발생“소수성과회복”.근거함유조조인자적접촉각수시간연변모형,득도료구유납미철점직구LDPE표면재불동노화온도하적가이동겁성기단소점면적분수( fpm )、고정겁성기단소점면적분수(fpim)화특정시간상수(자)3개성분중구삼수,해석료“소수성과회복”현상.
Low density polyethylene ( LDPE ) surface was modified by oxygen capacitively coupled plasma ( CCP) under a radio frequency( RF) power of 200 W for an exposure time of 1 min. The aging process of the plasma-modified LDPE was studied at aging temperatures of 60 and 90 ℃ for an aging time of 24 h. The mor-phology with the nanonodules was obtained on the as-modified LDPE surface under 200 W for 1 min and was stable on the post-aged LDPE surface at 60 and 90 ℃ after 24 h. The plasma modification under 200 W for 1 min introduced lots of polar oxygen-containing groups on the as-modified LDPE surface. The aging process at 60 ℃ after 24 h aroused the decrease of the polar oxygen-containing groups on the post-aged LDPE surface and lower oxygen-containing group content appeared on the post-aged surface at 90 ℃. The as-modified hydrophi-lic surface with the contact angle of 42.3ounderwent the hydrophobic recovery into hydrophobicity on the post-aged surface with the contact angle of 95.9o at 60 ℃ after 24 h similar to the original LDPE surface with 97.2o, and further hydrophobic over-recovery into higher hydrophobicity of the post-aged surface with the con-tact angle of 104.2o at 90 ℃ after 24 h than the original surface. Based on the time-dependent contact angle model for the aging of the rough surface containing different wetting patches, the surface restructuring on the plasma-modified LDPE surface experiencing the hydrophobic over-recovery during aging process was quantita-tively analysized.