Surface Coating Applications

Nanocellulose-reinforced acrylate latex can also be an interesting material for the surface coating industry. Mabrouk et al. [57] used an one-step miniemulsion polymerization method to prepare stable aqueous nanocomposite dispersions based on cellulose whiskers extracted from the rachis of the date palm tree and a poly (styrene-co-2-ethyl hexylacrylate) copolymer. A reactive silane, i.e., methacryloxypropyl triethoxysilane (MPS) was added to stabiHze the dispersion and favor the anchoring of the whiskers on the polymer particles. The particle size of the polymer dispersion ranged between 90 and 160 nm for a whisker content varying from 1 to 5 wt%. 

It was evident that with 1 wt% MPS, the reinforcing aptitude of the whiskers was much higher than that reached when using 3 wt% MPS. At such a level, the presence of MPS prevented the formation of a rigid percolating whiskers network through strong 

An interesting work was carried out by Banerjee et al. [65] in the area of in-situ polymerized cellulose nanocomposites. They surface treated extracted cellulose nanofibers with methyl methacrylate monomer (MCNF) and PMMA/cellulose nanocomposites (MMIPC) were formed by in-situ suspension polymerization process. 

The crystalline structures of cellulose in the composites were mostly disrupted indicating good compatibility between cellulose and the polymeric ionic liquids. The mechanical properties of the composites were changeable by changing the weight ratios of the two polymerizable ionic liquids [66]. 

---

Of the higher vinyl ester homopolymers only poly(vinyl propionate) is currently believed to be of commercial value, being marketed as Propiofan (BASF) for surface coating application where greater alkali resistance is possible than with the normal vinyl acetate based copolymers. 

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. 

About half of epoxide resin production is used for surface coating applications, with the rest divided approximately equally between electronic applications (particularly for printed circuit boards and encapsulation), the building sector and miscellaneous uses. In tonnage terms consumption of epoxide-fibre laminates is only about one-tenth that of polyester laminates, but in terms of value it is much greater. 

For a number of purposes the unmodified epoxide resins may be considered to have certain disadvantages. These disadvantages include high viscosity, high cost and too great a rigidity for specific applications. The resins are therefore often modified by incorporation of diluents, fillers, and flexibilisers and sometimes, particularly for surface coating applications, blended with other resins. 

Tertiary amines such as benzyldimethylamine, 2-(dimethyl aminoethyl) phenol, etc. form an anion with epoxide which leads to their polymerisation. These are used mainly for adhesives and surface coating applications. 

Cellulose nitrate film cast from solution is highly brittle and is made flexible for surface coating applications bv the addition of plasticizers like dibutylphthalate, dioctylphthalate,... 

Exploiting Acrylic Polymer Architecture in Surface Coatings Applications... 

This can be viewed either starting from the top left (technology push) or the bottom (market pull). Starting with synthesis, why alter polymer composition Control of polymer chemistry and synthesis leads to a defined polymer architecture, i.e. the chemical and physical composition of a polymer chain. This architecture influences the basic properties of bundles of polymer chains, which then correlate with applied properties. The polymerisation process may affect the polymer architecture produced and the coating process will influence both the basic and applied properties. Basic properties are independent of the application whereas applied properties may be application specific. For surface coatings applications, the overall performance will be influenced by other raw materials in the formulation, depending on the nature of the individual components and the interaction between them. Improvement in specific... 

Figure 9. Epoxy resins in surface coating applications.

Polyurethane systems are also formulated for surface-coating applications. A wide range of such products has become available. These include simple simple solutions of finished polymer (linear polyurethanes), One component systems containing blocked isocyanates, two-component systems based on polyester and isocyanate or polyether and isocyanate, and a variety of prepolymer and adduct systems. 

The conducting solution of a monomer, in a suitable solvent or a melted conducting monomer, undergoes electrolysis to generate reactive species. The polymer is formed on one electrode, depending on the ionic nature of the active species. This technique is mainly used for surface coating applications to protect metal electrodes or to obtain conductive polymer electrodes. 

S. S. Mahapatra and N. Karak, Synthesis and characterization of polyesteramide resins from Nahar seed oil for surface coating applications . Prog Org Coat, 2004,51,103-8. 

Surface Coatings Applications of Hydrogels. The surface treatment of polymeric materials is one of the most active research areas in the field of biomedical materials. It is generally agreed that the surface of any material is what dictates its cellular response in the body. Attempts to design biocompatible... 

---