Search results
Results from the WOW.Com Content Network
However, in practice a dynamic phenomenon of contact angle hysteresis is often observed, ranging from the advancing (maximal) contact angle to the receding (minimal) contact angle. [1] The equilibrium contact is within those values, and can be calculated from them. The equilibrium contact angle reflects the relative strength of the liquid ...
Figure 1: Schematic of a measured contact angle for a liquid on a solid substrate. Where θ is the contact angle denoted also in this case by θ SL . Even though this relationship is empirical and less precise than the surface tension of a homologous series of liquids, it is very useful considering it is a parameter of the solid surface.
The most common form of cellulose acetate fiber has an acetate group on approximately two of every three hydroxyls. This cellulose diacetate is known as secondary acetate, or simply as "acetate". After it is formed, cellulose acetate is dissolved in acetone, forming a viscous solution for extrusion through spinnerets (which resemble a shower ...
The most common way to prepare cellulose acetate phthalate consists of the reaction of a partially substituted cellulose acetate (CA) with phthalic anhydride in the presence of an organic solvent and a basic catalyst. The organic solvents widely used as reaction media for the phthaloylation of cellulose acetate are acetic acid, acetone, or ...
Cellulose acetate butyrate (CAB) is a mixed ester thermoplastic derivative of cellulose acetate that contains both acetate and butyrate functional groups. It has improved weathering resistance and lower moisture absorption compared to cellulose acetate.
Cassie's law, or the Cassie equation, describes the effective contact angle θ c for a liquid on a chemically heterogeneous surface, i.e. the surface of a composite material consisting of different chemistries, that is, non-uniform throughout. [1] Contact angles are important as they quantify a surface's wettability, the nature of solid-fluid ...
Cellulose diacetate film was first created by the German chemists Arthur Eichengrün and Theodore Becker, who patented it under the name Cellit, from a process they devised in 1901 for the direct acetylation of cellulose at a low temperature to prevent its degradation, which permitted the degree of acetylation to be controlled, thereby avoiding total conversion to its triacetate.
Triacetate, whose chemical formula is [C 6 H 7 O 2 (OOCCH 3) 3] n, was first produced commercially in the U.S. in 1954 by Celanese Corporation. Eastman Kodak was a manufacturer of CTA until March 15, 2007.