私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

A super-hydrophobic surface with excellent wear and salt spray resistance was prepared based on bisphenol A-aniline benzoxazine (BA-a), mesoporous material (SBA-15) and imidazole. The mechanism for these resistances was explored. Density gradient structures, organic–inorganic interpenetrating networks and self-similar structures formed in BA-a/SBA-15/imidazole. The tin sheeting surface coated with BA-a/SBA-15/imidazole hardly changed after 10 days of salt spraying, but its contact angle decreased to lower than 90°. After soaking and heat treatment, the contact angle recovered to 168° ± 2°.