Water Based Silicone 2
An important property of silicone SAA is its excellent surface activity and ease of spreading. This property is derived from the low surface tension and weak intermolecular forces of polydimethylsiloxane. The silicon atom is in the center of the tetrahedron in the compound. According to the tetrahedral structure, the two methyl groups are perpendicular to the plane in which the silicon and two adjacent oxygen atoms are connected; since the SI-C bond has a large length, the three hydrogens on the two non-polar methyl groups are like an open umbrella, so that it has good hydrophobicity.
The three hydrogen atoms on the methyl group occupy a large space due to the rotation of the methyl group, thereby increasing the distance between adjacent siloxane molecules; the intermolecular force is inversely proportional to the sixth power of the intermolecular distance, so polydimethylsiloxane has much weaker intermolecular forces than hydrocarbons. Therefore, its surface tension is smaller than that of hydrocarbons of similar molar mass, so that the siloxane is easily spread at the interface. Another reason for polydimethylsiloxane chain distribution and polar surfaces (such as water, metals, fibers, etc.) is that oxygen in the silicon oxide chain forms hydrogen bonds with polar molecules or radicals. The force of the molecules between the silicon oxide chain and the polar surface is increased, causing it to spread into a monolayer; thus making the hydrophobic silicone lying on the polar surface in a unique "extension chain" configuration. The hydrophobic group of a common SAA is erected on a polar surface.
The above characteristics of silicone SAA determine that such materials have the characteristics of easy emulsification, excellent permeability, strong bonding with polar substrates, good surface spreadability, and thin film formation. If it is not modified by a hydrophilic group, it is still hydrophobic.
A typical type of silicone SAA is a polyether silicone oil. Since the polyether group is suspended or embedded in its molecular chain (side chain or main chain), it has a property of being oleophilic and hydrophilic. That is, the oil is not only miscible with the alkane oily substance, but also easily dispersed in water. This is a very useful feature.
- October 17, 2018(1) Silicone gel can be used as a desiccant and can be reused. Silicone gel is a porous material having a different particle size which is suitably dehydrated from a silicic acid gel mSiO2·nH2O. It h...view
- October 17, 2018(1) The silicone sealant has stable quality and long-lasting effect, unlike the acrylic system. As a result, they are extremely cost-effective, especially when used in kitchens and bathrooms. Silicone...view
- May 25, 2018Single component RTVSingle component RTV silicone rubber system is one of the three RTV silicone rubber system that is used most widely. The silicone rubber can be turned into elastomer with net struc...view
- August 16, 2018The silicone solvent is a milky white or light cyan transparent solution, and the basic component is amorphous silica. Its molecular formula is mSiO2•nH2O, wherein SiO2 is dispersed in water or an or...view
- October 17, 2018(1) Silicone sealant for construction is widely accepted as the waterproof sealing material widely used in interior and exterior decoration of various buildings. However, with the rapid development of...view
- December 19, 2017On November 25th, 2016, Shenzhen, Hong Kong and Macao alumni from Nanjing University of Aeronautics and Astronautics visited Tianyongcheng polymer materials (Changzhou) Co., Ltd. And they provided gui...view