Plasticizer polymeric binder

Paints are complex formulations of polymeric binders with additives including anti-corrosion pigments, colors, plasticizers, ultraviolet absorbers, flame-retardant chemicals, etc. Almost all binders are organic materials such as resins based on epoxy, polyurethanes, alkyds, esters, chlorinated rubber and acrylics. The common inorganic binder is the silicate used in inorganic zinc silicate primer for steel. Specific formulations are available for application to aluminum and for galvanized steel substrates. 

A number of plastic-bonded expls based on HMX RDX plus polymeric binders has been developed at the Lawrence Livermore Lab, University of California, Livermore. Their props have been compiled by Dobratz (Ref 2)... 

Process Steps. Casting powder manufacture is basically a plastics-forming operation, utilizing a volatile solvent to impart mobility to the polymeric binder. The process is shown schematically in Figure 2 in terms of the major equipment used. For discussion, the process may be divided conveniently into the following operations ... 

Solid propellant compositions which have been previously discussed all sulfer from the possibility of accidental initiation from fire, impact, electric spark, etc. Therefore, attention has turned to the development of insensitive munitions with particular emphasis on low vulnerability ammunition (LOVA). LOVA propellants contain RDX or HMX, an inert polymeric binder and a plasticizer. These composite propellants are less vulnerable to initiation than nitrocellulose-based propellants. 

Composite rocket propellants are two-phase mixtures comprising a crystalline oxidizer in a polymeric fuel/binder matrix. The oxidizer is a finely-dispersed powder of ammonium perchlorate which is suspended in a fuel. The fuel is a plasticized polymeric material which may have rubbery properties (i.e. hydroxy-terminated polybutadiene crosslinked with a diisocyanate) or plastic properties (i.e. polycaprolactone). Composite rocket propellants can be either extruded or cast depending on the type of fuel employed. For composite propellants which are plastic in nature, the technique of extrusion is employed, whereas for composite propellants which are rubbery, cast or extruded techniques are used. 

Polymer thick films also perform conductor, resistor, and dielectric functions, but here the polymeric resins remain an integral part after curing. Owing to the relatively low (120—165°C) processing temperatures, both plastic and ceramic substrates can be used, leading to overall low costs in materials and fabrication. A common conductive composition for flexible membrane switches in touch keyboards uses fine silver particles in a thermoplastic or thermoset polymeric binder. 

Because spiropyrans (and especially BIPS) are relatively easy to prepare, a variety of compounds are available from which to deduce correlations (usually semiempirical Hammett-like equations) between structure and photochromic parameters in dilute fluid solutions. The photochromic behavior of a single dye in a variety of solvents can also be correlated with a solvent parameter such as. In applications, however, the dyes are almost always relatively concentrated in a bulk polymer or a polymeric binder film, and various other additives such as antioxidants, surfactants, fire retardants, plasticizers, and other colorants are also present. Under these conditions, the observed photochromic behavior is often very different from that predicted by the dilute fluid solution correlations. 

A ceramic suspension consists of ceramic powder, a solvent, often a dispersant to stabilize the ceramic powder ag2iinst a omeration, a polymeric binder to provide green strength after the green body has been dried, and often a plasticizer to lower the glass transition of the polymeric binder. All these additives must be compatible so the ceramic suspension has the desirable properties needed for green body fabrication. Many of these formulations used in industry are very secretive. 

In some cases, an extrudable and injectable paste may consist of 65% vol. ceramic powder and 35% vol. polymeric binder. In others, an extrudable paste may consist of a highly loaded aqueous suspension of clay particles such that its rheology is plastic. Hie low shear (i.e., <100 sec ) viscosity of such a paste is between 2000 and 5000 poise at ambient temperature. Highly nonlinear stress strain curves are typical of ceramic pastes, as well as time dependent thixotropy. In many cases, pastes behave like visco-elastic fluids. This complex rheological behavior of ceramic pastes has made theoretical approadies to these problems difficult. For this reason, the discussion in this chapter is limited to Newtonian fluids where analytical solutions are possible, with obvious consequences as to accuracy of these equations for non-Newtonian ceramic pastes. 

Composite rocket propeiiants. This type of propellant contains two-phase mixtures with a aystalhne oxidizer in a polymeric fuel or binder matrix. The finely dispersed powder of ammonium perchlorate suspended in a fuel is the oxidizer. The fuel is a plasticized polymeric material such as hydroxy-terminated polybutadiene cross-linked with a diisocyanate (rubber ts e) or carboxy-terminated polybutadiene (plastic type) [4]. 

Also, the preparation of honeycomb plastics and gas-filled fibrous materials does not require foaming. Formation of gas cavities in the former is carried out by glueing of previoudy prepared sheet materials or by extmsion of thermoplastics through special nozzles in the latter case by glueing or filling with polymeric binders of fibrous substances containing capillaries and pores. 

Antimony pentoxide, as an additive for plastic materials such as polyolefins and ABS, is produced in predispersed form containing halogen compounds and a polymeric binder which has a low melting index to aid incorporation. 

The primary focus of this chapter is to describe the factors that influence flow behavior and mix homogeneity of a plastic mixture containing a high volume fraction of ceramic powder as a filler and a relatively small volume fraction of organic polymeric binder. The emphasis is placed on mixes in which flowability is achieved only above the ambient temperature. 

Propellants are explosive materials with low rates of combustion diat will ideally burn at uniform rates after ignition without requiring interaction with the atmosphere [1,2], They frequently involve several components, including an energetic oxidizer, a plasticizer to facilitate processing, and a polymeric binder. The specific impulse of such propellants is necessarily that of the composite mixture. Oui focus here is on chemical and structural factors affecting the specific impulse of the oxidizer, which will be designated as a monopropellant. 

Fibre reinforced plastics are commonly fabricated by embedding small diameter fibres with relatively high strength and stiffness into a relatively ductile polymeric binder or matrix. The main functions of this matrix material are to maintain the overall shape and geometry, to transfer the inplane shear and transverse loads from one fibre to another, and to transfer... 

---