Waxes wettability

The application of surface treatments to mbbers should produce improved wettability, creation of polar moieties able to react with the adhesive, cracks and heterogeneities should be formed to facilitate the mechanical interlocking with the adhesive, and an efficient removal of antiadherend moieties (zinc stearate, paraffin wax, and processing oils) have to be reached. Several types of surface preparation involving solvent wiping, mechanical and chemical treatments, and primers have been proposed to improve the adhesion of vulcanized SBR soles. However, chlorination with solutions of trichloroisocyanuric acid (TCI) in different solvents is by far the most common surface preparation for mbbers. 

Caustic boil assistant for cellulosics and blends. Improves wettability, whiteness and decreases fiber degradation. Solubilizes waxes and other impurities for more level dyeing. 

Sustained release wax matrix tablets are generally considered difficult to coat with aqueous polymeric dispersions due to the poor wettability of the hydrophobic tablet surface. "" The physicochemical... 

Several woody plant species will react to exposure of simulated acid rain by forming foliar lesions. While the pH level of simulated acid rain that produced these lesions varies from species to species, the lesions themselves are generally yellow to brown necrotic spots or regions (see Table 1). Additionally, on two clones of poplar, galls were formed in response to simulated acid rain. Surface characteristics such as stomatal presence and density, trichome density, type and amount of epicuticular wax, leaf surface wettability and buffering capacity have all been shown to influence foliar injury by simulated acid rain. However, it may be... 

Paper wettability by polystyrene based toner has been studied by Lee (3). Wax/polymer coating of paper and paperboard has been investigated by Swanson and Becher (4), Glossman (5 ), and more recently by Fredholm and Westfelt (60. In the coating studies it was believed that surface energetics of the paper structure played a fundamental role in the spreading process and subsequent adhesion of polymer to the paper surface. 

Until now, no experimental studies have yet been published on supercritical melt micronisation for fats. The aim of this work is to develop and to understand a process for the micronisation of edible fats, polymer or waxes. The requirements for such powders are from manufacturers and consumers different. For example, for a good dispersion of particles in solutions the particles should not be too small or hollow always, because flotation of the particles appears at the surface of the solution. Another application is the wettablity of the powder, where non-spherical particles with large surfaces areas are required. 

N-Methylpyrrolidone [872-50-4] (NMP) has a fairly mild, amine-like odor, and is miscible with water and most organic solvents. It has a good solvency for cellulose ethers, butadiene-acrylonitrile copolymers, polyamides, polyacrylonitrile, waxes, polyacrylates, vinyl chloride copolymers, and epoxy resins. It is used in paint removers and stripping paints to reduce paint viscosity, and to improve the wettability of paint systems. A -Methylpyrrolidone is also employed for the extraction of hydrocarbons, and as a solvent in the synthesis of acetylene. 

The increased erosion (weathering) of plant cuticles by simulated "rain acidified with sulfuric acid may disrupt processes that occur at the leaf surface. The most important function of the cuticle is to reduce water (transpiration) loss. > Removal of leaf surface waxes has been reported to increase wettability of those surfaces.Leaves which had been wetted and dried are subsequently wetted more easily.The water repellency of a plant surface is important in preventing the establishment of infections from water-borne inocula.Dickinson proposed that the thigmotropic response of germ tubes of certain fungi is a function of the structure and thickness of the cuticle. Both of these features of cuticular waxes appear to be altered by simulated rain acidified with sulfuric acid. The apparent loss of surface... 

Dhiman and Chandra [41] photographed impact of water droplets on surfaces of different wettability at impact velocities up to 30 m/s. Figure 8.8 shows three different sequences of the impact of water droplets on a wax surface at three different impact velocities 10 m/s, 20 m/s and 30 m/s. Each vertical column shows successive stages of impact at one of the velocities, which yielded Reynolds numbers (Re) of 5,800, 11,600, and 17,400 respectively. Droplets flattened into a thin film after impact as they reached their maximum extension, followed by retraction until they eventually attained equilibrium. The diameter of the films at maximum extension increased with Re and hence their thickness decreased. Holes were formed in each film that grew larger, rendering the film unstable. 

When the contact surfaces are greatly different in wettability (hydrophilic quartz particles on a hydrophobic paraffin wax substrate, or mastic or graphite particles on a quartz surface), the adhesion is minimal (adhesion number equal to zero). 

In addition to its influence on surface reactivity, surface structure is also seen to affect wettability on the micrometer scale, as is best illustrated by the lotus effect (see Chapter 3b). The lotus leaf is superhydrophobic, i.e. has a water contact angle of about 160°, thanks to the combination of the waxes on the surface with a characteristic dual micrometer- and nanometer-scale surface topography. Without the structure, the wax chemistry would only impart mild hydrophobicity to the surface. Superhydrophobicity comes about only when a water droplet is in contact with a rough surface with a substantial enclosure of air beneath the drop (Figure 9). This is the so-called Cassie-Baxter state, named after the authors of the work that described the contact angle of water droplets in this state by means of the equation ... 

RWM type b is semi-crystalline material and needs up to 5 min to build up the required handling strength. After this open time, the wettability ends and simultaneously high forces are built up in the adhesive material. Solidification results in shrinkage and leads to stress cracks at the interface of the bonding and in the adhesive. It behaves like candle wax. The cut-off string is minimal, since a short chain semi-crystalline binder is used. 

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