Melamine plastic powder

Mouldings from melamine-formaldehyde powders are superior to the urea-formaldehyde plastics in a number of respects. 

Melamine cyanurate powder, containing nearly 50% of nitrogen can be used as an additive to polyamide 6 at the melt stage before fibre spinning or plastics production. The addition of MC lowers the specific tenacity of the fibres but decreases the flammability. This latter effect is stronger in solid plastics than for fibres. 

For mix number 1, to determination the primal proportion of melamine plastic content in the composition. The concrete was composed of cement, sand, melamine, and plastic, adjusted to 1.0 1.0 1.0-3.0. The plastic proportion was increased in increments of 0.5. The water and aluminum powder were taken as 0.35 and 0.004 by weight of cement, respectively. 

For mix number 2, to determine the optimum propoition of sand, the quantities of sand by weight of cement were varied from 1.0 to 1.8 with an increment of 0.2 for each step. The portions of other materials were kept constant. That is the proportion of cement, alumimun powder, water, and melamine plastic was adjusted to 1.0 0.004 0.35 1.0. 

Based on the results, the optimmn proportions of materials are cement aluminmn powder water sand melamine silica fume superplasticizer equal to 1.0 0.004 0.35 1.4 2.0 0.25 0.007. However, the optimum proportions of materials for the studied by [4] were cement, sand, water, fly ash, aluminum powder, and melamine equal to 1.0 0.8 0.75 0.3 0.0035 0.9. Therefore, the used of melamine plastic more than previous study (about 122%) for non-load-bearing lightweight concrete according to ASTM C129 lype II standard. Also, the dry density of non-load-bearing hghtweight concrete was reduction by 36.4% in comparison with the previous study. 

Cement Aluminum powder Water Sand Melamine Silica fume Superplasticizer FIGURE 14 Absorption after immersion and voids for varying melamine plastic content (curing for 28 days). 

The term aminoplastics has been coined to cover a range of resinous polymers produced by interaction of amines or amides with aldehydes. Of the various polymers of this type that have been produced there are two of current commercial importance in the field of plastics, the urea-formaldehyde and the melamine-formaldehyde resins. There has in the past also been some commercial interest in aniline-formaldehyde resins and in systems containing thiourea but today these are of little or no importance. Melamine-phenol-formaldehyde resins have also been introduced for use in moulding powders, and benzoguanamine-based resins are used for surface coating applications. 

As with the U-F moulding powders the relative importance of M-F moulding powders for other plastics materials and also in other uses for melamine-formaldehyde resins has declined. 

UREA-FORMALDEHYDE RESIN. An important class of amino resin. Urea and formaldehyde are united in a two-stage process in the presence of pyridine, ammonia, or certain alcohols with heat and control of pH to form intermediates (methylolurea, dimenthylolurea) that are mixed with fillers to produce molding powders. These are converted to thermosetting resins by further controlled heating and pressure in the presence of catalysts. These were first plastics that could be made in white, pastel, and colored products. See also Amino Acids Melamine. 

In-mold decoration can be done with either injection molding of thermoplastics or compression molding of thermosets. Thermosetting plastics are decorated with a two-stage process. For melamine products, for example, the mold is loaded with the molding powder in the usual manner and closed. It is opened after a partial cure, and the decorative "foil or overlay is placed in position. 

---