Room temperature curable inorganic–organic hybrid nanocomposite hydrophobic coating: mechanistic understanding of the role of Ti(iv) and the diamine based curing agent

Abstract

Room temperature curable inorganic–organic hybrid nanocomposite single layered transparent hard hydrophobic coatings have been developed by sol–gel spray coating process.

Room temperature cured silver nanoparticle embedded hybrid nanocomposite coatings: processing and property evaluation

“…GLYMO has polymerizable alkoxy groups as well as epoxy groups bonded with Si through –(CH 2 ) 3 –O– chains. 28 Therefore, during hydrolysis-condensation reactions, the alkoxy group results in a –Si–O–Si– network, whereas the epoxy group generates a polyethylene oxide (PEO) network. In this system, polydimethyl siloxane (PDMS) trimethylsiloxy terminated (MW 4000 gmol −1 ) is incorporated to enhance the hydrophobic surface by weak van der Waals interaction in the polymeric network.…”

“…The bands at 2864–2947 and 1375–1455 cm −1 are attributed to C–H/CH 2 stretching and bending vibrations, respectively. 28,31,32 A broad stretching vibration at 3200–3500 cm −1 represents –OH and –NH, and their corresponding bending vibrations appear at 1600–1700 cm −1 . 31,32 The characteristic peaks in the skeletal system of the polymeric network at 1056, 913 and 785 cm −1 are due to Si–O–Si/Ti–O–C, and the corresponding C–O stretching vibration is at 1276 cm −1 .…”

“…31,32 The characteristic peaks in the skeletal system of the polymeric network at 1056, 913 and 785 cm −1 are due to Si–O–Si/Ti–O–C, and the corresponding C–O stretching vibration is at 1276 cm −1 . 28,32–34 It is worth noting that the intensity of the N–H bending vibration is reduced in the embedded Ag NPs in the polymeric network structure, which is due to the interaction between amino groups and Ag NPs. 33 In the solution stage, the peak intensity of –NH bending at 1630 cm −1 appeared low due to chemical interactions with other species (Fig.…”

“…This method was adopted as per a survey of the literature. 28,41,42 In this test, 80 mesh sand paper was positioned on the coated surface with a load of 100 g weight and observed upon pulling the sand paper at a 180° angle across a 4 cm travel distance on the coated surface for up to 30 cycles. A change of the WCA value from 101° (before the abrasion test) to ∼92° (after 20 cycles) was observed, and it reached 65° after 30 cycles (Fig.…”