Acrylic resin-clay

In one example, a quaternary ammonium salt of dimethylaminoacry-lamide (Q modified monomer of acryUc resin) was ion-bonded to silicate layers, while ethyl acrylate (EA) and acrylic acid (Aa) were copolymerized in the clay gallery. The ratio between the EA and the Aa was 10 1 (molar ratio). Eour kinds of acrylic resin-clay nanocomposites were polymerized. Their clay contents were 1, 3, 5 and 8 wt % on the basis of the solid acryhc resins. Suspensions with greater than 3 wt % clay addition acted as pseudoplastic fluids. Transparent acrylic resin-clay nanocomposite films cross-Hnked by melamine... 

There are also some other reports of acrylic resin-clay nanocomposites. A poly(methylmethacrylate) clay nanocomposite was synthesized using a modified organophilic clay in the same manner [8], and by emulsion polymerization [9]. Figure 2 shows a schematic representation of this polymerization method. 

It was recently shown that clay/acrylate nanocomposite polymers can be easily synthesized by UV-radiation curing of multiacrylate monomers containing silicate nanoparticles. As Chapter 6 deals with conventional clay/ acrylate nanocomposites, we will restrict the scope of this chapter to the highly crosslinked nanocomposite materials obtained by photopolymerization of clay-based acrylate resins. The overall process is represented schematically in Fig. 7.1. 

A typical formulation of a photocurable composite resin contains four basic components a radical-type photo initiator, an acrylate functionalized oligomer, a reactive diluent and the clay mineral filler. The photoinitiator is usually an aromatic ketone which cleaves into two radical fragments upon UV exposure. The telechelic oligomer consists of a short polymer chain (polyurethane, polyether, polyester) end-capped by the very reactive acrylate double bond. An acrylate monomer is generally used as reactive diluent to reduce the resin viscosity. Figure 7.2 shows some typical compounds used in UV-curable acrylic resins. Different types of phyllosilicates were selected as mineral filler an organophilic clay (Nanomer I-30E from Nanocor), native hydrophilic clays (montmorillonite KIO and bentonite) and a synthetic clay (beidellite). 

K. Zahouily, C. Decker, S. Benfarhi, J. Baron, A novel class of hybrid organic clay UV-curable nanocomposite materials , Proc. RadTech America 2002, pp. 309-318. L. Keller, C. Decker, K. Zahouily, S. Benfarhi, J.M. Le Meins, J. Miehe-Brendle, Synthesis of polymer nanocomposites by UV-curing of organoclay-acrylic resins , Polymer, 2004, 45, 7437-7447. 

Fluid loss additives such as solid particles and water-thickening polymers may be added to the drilling mud to reduce fluid loss from the well bore to the formation. Insoluble and partially soluble fluid loss additives include bentonite and other clays, starch from various sources, crushed walnut hulls, lignite treated with caustic or amines, resins of various types, gilsonite, benzoic acid flakes, and carefully sized particles of calcium borate, sodium borate, and mica. Soluble fluid loss additives include carboxymethyl cellulose (CMC), low molecular weight hydroxyethyl cellulose (HEC), carboxy-methYlhydroxyethyl cellulose (CMHEC), and sodium acrylate. A large number of water-soluble vinyl copolymers and terpolymers have been described as fluid loss additives for drilling and completion fluids in the patent literature. However, relatively few appear to be used in field operations. 

The manufacture of paper and allied products involves the preparation of wood and other raw materials, separation and recovery of cellulose fibers, and blending of the fibers with proper additives to produce furnish , which is formed into paper. The additives include sizing materials such as alum and resins, sodium aluminate, and wax emulsions synthetics, such as acrylics, isocyanates, and fiuocarbons and fillers such as clays, calcium carbonate and sulfate, talc, barium sulfate, aluminum compounds, and titanium oxide. When fillers are used, retention aids (starches or synthetic resins) are added to increase the retention of the filler. 

This technique has found the following applications in addition to those discussed in Sections 10.1 (resin cure studies on phenol urethane compositions) [65], 12.2 (photopolymer studies [66-68]), and 13.3 (phase transitions in PE) [66], Chapter 15 (viscoelastic and rheological properties), and Section 16.4 (heat deflection temperatures) epoxy resin-amine system [67], cured acrylate-terminated unsaturated copolymers [68], PE and PP foam [69], ethylene-propylene-diene terpolymers [70], natural rubbers [71, 72], polyester-based clear coat resins [73], polyvinyl esters and unsaturated polyester resins [74], polyimide-clay nanocomposites [75], polyether sulfone-styrene-acrylonitrile, PS-polymethyl methacrylate (PMMA) blends and PS-polytetrafluoroethylene PMMA copolymers [76], cyanate ester resin-carbon fibre composites [77], polycyanate epoxy resins [78], and styrenic copolymers [79]. 

Floor-covering adhesives are used for gluing down flexible floor coverings, such as carpet or vinyl sheet. In Europe predominantly acrylics are used, formulated with tack-ifying resins and calcium carbonate as filler. In North America usually high solids content styrene-butadiene emulsion polymers are applied, formulated with naphthenic oil and clay as filler (Urban Egan, 2002). In either formulation the inorganic filler content is between 25% and 50% and the polymer/resin ratio is about 1. 

This book covers both fundamental and applied research associated with polymer-based nanocomposites, and presents possible directions for further development of high performanee nanocomposites. It has two main parts. Part I has 12 chapters which are entirely dedicated to those polymer nanocomposites containing layered silicates (clay) as an additive. Many thermoplastics, thermosets, and elastomers are included, such as polyamide (Chapter 1), polypropylene (Chapter 4), polystyrene (Chapter 5), poly(butylene terephthalate) (Chapter 9), poly(ethyl acrylate) (Chapter 6), epoxy resin (Chapter 2), biodegradable polymers (Chapter 3), water soluble polymers (Chapter 8), acrylate photopolymers (Chapter 7) and rubbers (Chapter 12). In addition to synthesis and structural characterisation of polymer/clay nanocomposites, their unique physical properties like flame retardancy (Chapter 10) and gas/liquid barrier (Chapter 11) properties are also discussed. Furthermore, the crystallisation behaviour of polymer/clay nanocomposites and the significance of chemical compatibility between a polymer and clay in affecting clay dispersion are also considered. 

In earlier times physical prototypes may have been hand carved out of wood or molded from clay. In modern times, polymers are the materials used most widely in RP applications. These materials include ABS, nylon, and UV-curable photopolymer resins such as epoxy, acrylates, and vinyl-ethers. This chapter describes the various techniques and devices nsed to produce RP parts and details of the polymer materials that are used. Advantages and disadvantages of different techniques such as accuracy and strength of the product are considered. 

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