Acrylic resin types

As mentioned above, both thermoplastic and thermosetting type acrylic resins are commercially available for coatings, elastomers, sealants and adhesive applications. These resins are supplied in many different delivery forms such as powders or pellets, solutions in organic solvents and aqueous dispersions. These resin types are briefly described below. 

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These requirements are usually met with two-pack paints based on hydroxyl-rich polyester or acrylic resins in the pigmented pack and aliphatic polyisocyanates in the activator pack. Cure with this type of finish is relatively fast and complete even at low ambient temperatures. An alternative finish is an acrylic lacquer, similar to the lacquer used for refinishing motor cars. These finishes are applied to the assembled aircraft by operators protected by air-fed hoods and using airless or conventional spray guns. High durability pigments are included. 

Unsaturated polyester finishes of this type do not need to be stoved to effect crosslinking, but will cure at room temperature once a suitable peroxide initiator cobalt salt activator are added. The system then has a finite pot life and needs to be applied soon after mixing. Such a system is an example of a two-pack system. That is the finish is supplied in two packages to be mixed shortly before use, with obvious limitations. However, polymerisation can also be induced by ultra violet radiation or electron beam exposure when polymerisation occurs almost instantaneously. These techniques are used widely in packaging, particularly cans, for which many other unsaturated polymers, such as unsaturated acrylic resins have been devised. 

Polyols and polyamines are the most important coreactants for isocyanates. As briefly outlined in Section 4.2.2, the two most common classes of urethane-grade polyols are the polyethers and polyesters. In this section their synthesis and structure are discussed. Other polyol types, such as acrylic resins and polycarbonates, are of more limited applicability and are not presented here. 

P.B.16 is used especially to produce metallic finishes. Incorporated in acrylate resin systems for this purpose, the pigment is weatherfaster than types of Copper... 

Experimental apparatus and procedure. Figure 1 is a schematic diagram of the experimental apparatus. The crystallizer was a 1 liter stirred tank reactor made of acrylic resin and is considered to be a continuous MSMPR reactor. The reactor was 0.1m in diameter and the liquid height 0.14m. The impeller used was of the 6-blade turbine type and operated at 450 rpm to... 

Under UV-laser irradiation, photosensitive multifunctional acrylate resins become rapidly cross-linked and completely insoluble. The extent of the reaction was followed continuously by both UV and IR spectroscopy in order to evaluate the rate and quantum yield of the laser-induced polymerization of these photoresist systems. Two basic types of lasers emitting in the UV range were employed, either a continuous wave (C.W.) argon-ion laser, or a pulsed nitrogen laser. 

Phenolics are consumed at roughly half the volume of PVC, and all other plastics are consumed in low volume quantities, mostly in single application niches, unlike workhorse resins such as PVC, phenolic, urea—melamine, and polyurethane. More expensive engineering resins have a very limited role in the building materials sector except where specific value-added properties for a premium are justified. Except for the potential role of recycled engineering plastics in certain applications, the competitive nature of this market and the emphasis placed on end use economics indicates that commodity plastics will continue to dominate in consumption. The application content of each resin type is noted in Table 2. Comparative prices can be seen in Table 5. The most dynamic growth among important sector resins has been seen with phenolic, acrylic, polyurethane, LLDPE/LDPE, PVC, and polystyrene. 

Sanitary ware, including tubs, showers, combined units, basins, and toilet tank, may be made of thermoformed ABS or acrylic sheet, molded glass-fiber-reinforced polyester, or cast acrylic resins. The glass-polyester type dominates the tub/shower market. It is possible to install the units as a two-component system, assembled in place. Gel coats may be of thermoformed decorative acrylic skins. To reduce the smoke generated by fire, methyl... 

The alcohols, proprietary denatured ethyl alcohol and isopropyl alcohol, are commonly used for E-type inks. Many E-type inks benefit from the addition of small amounts of ethyl acetate, MEK, or normal propyl acetate to the solvent blends. Aromatic hydrocarbon solvents are used for M-type inks. Polystyrene resins are used to reduce the cost of top lacquers. T-type inks are also reduced with aromatic hydrocarbons. Acrylic resins are used to achieve specific properties for V-type inks. Vehicles containing vinyl chloride and vinyl acetate copolymer resins make up the vinyl ink category. Ketones are... 

Phenolic-based resins have almost disappeared. A few other resin types are available commercially but have not made a significant impact. Inorganic materials retain importance in a number of areas where synthetic organic ion-exchange resins are not normally used. Only the latter are discussed here. This article places emphasis on the styrenic and acrylic resins that are made as small beads. Other forms of synthetic ion-exchange materials such as membranes, papers, fibers (qv), foams (qv), and liquid extractants are notincluded (see Extraction, liquid-liquid Membrane technology Paper.). 

Fig. 5. Pressure drop as affected by resin type, flow rate, and temperature, where A, B, and C, correspond respectively to acrylic strong base anion exchanger (Amberlite IRA-458), styrenic strong base anion exchanger (Amberlite IRA-402), and styrenic strong acid cation exchanger (Amberlite IR-120), all at 4°C. D represents styrenic strong acid cation resin (Amberlite IR-120) at 50°C (14). To convert kg/(cm2-m) to lb/(in.2ft), multiply by 4.33 to convert...

Temperatures should not exceed 60°C for the Type I resins, and 40°C for Type II and acrylic resins. Thermal degradation and the loss of functional groups occur when these temperatures are exceeded. Elimination of silica from the resin bed is further improved by preheating the bed with warm water before injecting the NaOH solution. 

Binding enzymes to solid supports can be achieved via covalent bonds, ionic interactions, or physical adsorption, although the last two options are prone to leaching. Enzymes are easily bound to several types of synthetic polymers, such as acrylic resins, as well as biopolymers, e.g., starch, cellulose [52], or chitosan [53,54]. Degussa s Eupergit resins, for example, are used as enzyme carriers in the production of semisynthetic antibiotics and chiral pharmaceuticals [55], Typically, these copolymers contain an acrylamide/methacrylate backbone, with epoxide side groups... 

There are basically two types of epoxy acrylate resins used in formulating adhesive systems. One is a vinyl ester resin that is used in two-component adhesive formulations much as a DGEB A epoxy or a polyester resin is. The other is a special type of resin that is used in radiation cure processes. This latter type of epoxy acrylate does not have any free epoxy groups, but reacts through its unsaturation. 

Primer A compatible coating designed to enhance adhesion. Redispersible powder Polymers typically produced by spray-drying isolation of the specially designed latex such as those of acrylics, vinyl acetate, etc. Depending on the nature of the resin type, a suitable amount of inorganic filler is added to the powders to prevent caking. 

Subsequently D Alello developed the polystyrene-hased resin in 1944 (4). Two years later, polystyrene anion-exchange resins made hy chloromethylation and amination of the matrix were produced. Four principal classes of ion-exchange resins were commercially availahle by the 1950s. These are the strong-acid, strong-hase, and weak-hase resins derived from styrene-divinylbenzene copolymers, and the weak-acid resins derived from cross-linked acrylics. To this day, the most widely used ion exchangers are synthetic organic polymer resins based on styrene- or acrylic-acid-type monomers as described by D Alelio in U.S. Patent 2,3666,007. 

Resins, types of polymers, are the thickening and hardening agents that, without pigments, serve as colorless nail protectors resembling clear furniture lacquer. These agents include nitrocellulose (collodion) and different acrylate and polyester/polyurethane copolymers. Copolymers include chemicals such as methacrylic acid, isobutyl methacrylate, toluenesulfona-mide formaldehyde resin, phthallic anhydride/trimellitic anhydride/glycol copolymer, tosylamide/formaldehyde resin, and dimethicone copolyol. 

There are two main types of barriers depth and screen. A depth filter retains particles both on its surface and within its matrix. Figure 37-6, p. 433, shows a depth filter made of fiberglass bonded with acrylic resin to prevent pieces from getting into the filtrate. Depth filters have a random matrix of fibers. The pore structure is irregular so they retain a variety of particle sizes. These filters are given a nominal rating, and they will retain 98% of all particles larger than that size. 

Since most of the applications of the PMMA type acrylic resins are based on their high degree of transparency and UV resistance characteristics, there has been little commercial interest or motivation in developing acrylic blends. This is understandable because unless there is complete, molecular level miscibility between the components, it is not possible to maintain a high degree clarity in the blends. Nevertheless, several examples of commercial blends of acrylic resins are known. These will be discussed under separate headings. 

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