Surface tension paints

In the treatment of plastics, the free radicals generated in the reaction chemically modify (ionize) the surface of the TPO thus allowing the color coat to attach itself to the polar TPO surface. The rest of the process is the same as in the Baseline above. QC method TPO surface 1/ FTIR 2/ surface tension Painted part 1/ cross-hatch adhesion 2/other tests. 

Several components of the organic phase contribute greatly to the character of the final product. The pore size of the gel is chiefly determined by the amount and type of the nonsolvent used. Dodecane, dodecanol, isoamyl alcohol, and odorless paint thinner have all been used successfully as nonsolvents for the polymerization of a GPC/SEC gel. Surfactants are also very important because they balance the surface tension and interfacial tension of the monomer droplets. They allow the initiator molecules to diffuse in and out of the droplets. For this reason a small amount of surfactant is crucial. Normally the amount of surfactant in the formula should be from 0.1 to 1.0 weight percent of the monomers, as large amounts tend to emulsify and produce particles less than 1 yam in size. 

Industrially, silicone surfactants are used in a variety of processes including foam, textile, concrete and thermoplastic production, and applications include use as foam stabilisers, defoamers, emulsifiers, dispersants, wetters, adhesives, lubricants and release agents [1]. The ability of silicone surfactants to also function in organic media creates a unique niche for their use, such as in polyurethane foam manufacture and as additives to paints and oil-based formulations, whilst the ability to lower surface tension in aqueous solutions provides useful superwetting properties. The low biological risk associated with these compounds has also led to their use in cosmetics and personal care products [2]. 

TPX has a very low surface tension around 24 mN m 1. For example, PE has a surface tension 01 31 mN m"1 and PTFE has a surface tension of 18 mNm-1. Because of its low surface tension, articles from TPX must be pretreated with e.g., corona, flame, plasma, etc., for printing, painting or bonding (16). 

Leafing and Nonleafing. Leafing pigments float on the surface of paint or printing ink films as a result of high interfacial tension. They form a coherent surface film whose reflective properties depend on the particle fineness. Stearic acid is the lubricant usually used in the manufacture of these products. 

The low surface tension of the majority of polymers makes them difficult to paint, to assembly with adhesives, or to print with inks. Table 5 gathers surface tension values of usual commodity plastics [203]. 

Silicone liquids in the production of paints. The use of silicone liquids as additives for paints gives them specific properties. E.g., an introduction of a small amount of silicone liquid (3 weight parts per 100 weight parts of the paint) prevents the foaming of paints when they are applied, improves the flow properties of the paint and gives gloss to the painted surface. This beneficial effect of oligoorganosiloxanes is caused by their low surface tension. 

Low surface tension (poor wettability ) may be a factor, with apparent repulsion of the paint and prevention of its rapid, even spread over the whole surface test inks of different values are available so that wettability can be assessed in advance with samples of the items concerned for satisfactory use with paints based on organic solvents, surface values of greater than 50 mN m 1 are desirable, and for water-based systems values greater than 70 mN m. ... 

F urther investigation of TNT with abnormal frothing showed that its surface tension (47 dynes/cm ) was only slightly lower than that for a std TNT (51 dynes/cm ), but there was also a sample of TNT with a low frothing value, which had an abnormally low surface tension (38 dynes/cm ). The viscosity of frothy TNT was of the same order as that of the std lot of TNT. Chemical analysis of frothy TNT did not indicate any difference from std TNT. It was found, however, that incorporation in std TNT of small amts of impurities, such as wax or grease increased the frothing value, but incorporation of 0.06% acid-proof black paint or 0.07% tetranitromethane... 

The nonleafing grade aluminum types are manufactured using oleic acid. They do not possess the required surface tension to leaf and consequently the aluminum platelets are randomly located within the paint film. The nonleafing grade is primarily used in automotive topcoats where they impart an aesthetically pleasing sparkle to the finish. 

A high electrical field apphed to a solvent emerging from a capillaiy canses the solvent to break into fine threads which disintegrate into small droplets. This phenomenon, nowadays called electrospray, was first described by Zeleny [44] in 1917. Uniform droplets in the 1-pm-lD range are prodnced in a breakup process that results from autorepulsion of the electrostatically charged surface, which overcomes the cohesive forces of surface tension. ESI nebnlization is widely used in painting, nuclear sciences, and spacecraft tluusters. 

Their low surface tension results in their utilization in the paint industry as flow, gloss and finish improvers. Silicone oil additives enable effect paints to be formulated such as moire effect paints. Their surface and interfacial activity enables their use as defoaming agents and as foam stabilizers for poly(urethane) foams. 

For self-releasing systems the presence of an IMR agent on the surface of the part, which makes It self-releasing, also lowers the value of the solid s critical surface tension, making It less wettable by the paint, than If It were free of the IMR surface coating. This problem, however, can be solved by either one of two ways (1) by the addition of solvent to the paint formulation that... 

Degreasing or solvent metal cleaning employs nonaqueous solvents to remove soils from the surface of metal articles that are to be electroplated, painted, repaired, inspected, assembled, or further machined. Metal work pieces are cleaned with organic solvents because water or detergent solutions exhibit a slow drying rate, electrical conductivity, high surface tension, a tendency to cause rusting, and a... 

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