Cyanoacrylic polyester

NoNaq"). The shear wave transducer for this sample was a 10 MHz lithium niobate transducer bonded with a cyanoacrylate polyester. For the lower density sample both PZT and quartz transducers operating at nominally 3 to 4 MHz were used for both longitudinal and shear wave propagation. They were bonded with either an alcohol-glycerine-based couplent or phenyl salicylate. The detected ultrasonic echoes were rectified and displayed on an oscilloscope equipped with time-delay circuitry for the transit time measurements. 

Types within group Cellulose acetate, cellulose acetate butyrate, cellulose nitrate, polyvinyl acetate, vinyl vinylidene, polyvinyl acetals, polyvinyl alcohol, polyamide, acrylic, phenoxy Cyanoacrylate, polyester, urea formaldehyde, melamine formaldehyde, resorcinol and phenol-resorcinol formaldehyde, epoxy, polyimide, polybenzimidazole, acrylic, acrylate acid diester Natural rubber, reclaimed rubber, bulyl, polyisobutylene, nitrile, styrene-butadiene, polyurethane, polysulfide, silicone, neoprene Epoxy-phenolic, epoxypolysulfide, epoxy-nylon, nitrile-phenolic, neoprene-phenolic, vinyl-phenolic... 

Flexible linear macromolecules make up, as mentioned before, the newest class of molecules and are the molecules most important to man. Their number is practically unlimited. For examples, almost all textile fibers are flexible macromolecules, from cotton, silk, wool, hair, and rayon to nylon, polyesters, and aramid. Many structural materials are also flexible macromolecules, such as lumber, compmsites, polyoxyethylene, poly(vinyl chloride), and nylon. Because of the ease of melting, many flexible macromolecules have earned the name plastics, such as polyethylene, polypropylene, polytetra-fluoroethylene, and polyoxides. Many adhesives such as glues, epoxides, poly-(vinyl alcohol), cyanoacrylic polyesters, and ethylene-vinyl alcohol copolymers are based on flexible macromolecules. The unique combination of viscosity and elasticity in the liquid state makes many flexible macromolecules useful as elastomers, of which natural and synthetic robbers and segmented polyurethanes are best known. Class 2 also includes the biolo cal macromolecules carbohydrates, proteins, and DNA. The biological macromolecules alone are practically unlimited in number, as documented by the variety of forms of life. 

In order to become useful dmg delivery devices, biodegradable polymers must be formable into desired shapes of appropriate size, have adequate dimensional stability and appropriate strength-loss characteristics, be completely biodegradable, and be sterilizahle (70). The polymers most often studied for biodegradable dmg delivery applications are carboxylic acid derivatives such as polyamides poly(a-hydroxy acids) such as poly(lactic acid) [26100-51-6] and poly(glycolic acid) [26124-68-5], cross-linked polyesters poly(orthoesters) poly anhydrides and poly(alkyl 2-cyanoacrylates). The relative stabiUty of hydrolytically labile linkages ia these polymers (70) is as follows ... 

Typical surface preparation calls for cleaning with acetone, MEK, or other common solvent. Once clean, the substrate is then mechanically abraded with sand, grit or vapor blast, or steel wool. The surface is again wiped clean with fresh solvent. Typical adhesives that are employed include epoxies, urethanes, and cyanoacrylates. Polysulfides, furanes, and polyester adhesives have also been suggested. 

Epoxies, isocyanate cured polyester, and cyanoacrylates are used to bond acetal copolymer. Generally, the surface is treated with sulfuric-chromic acid. Epoxies have shown 150- to 500-psi shear strength on sanded surfaces and 500- to 1000-psi on chemically treated surfaces. Two-component epoxies give slightly lower bond strengths. However, they bond acetal to itself and to many other materials. 

Polystyrene Although polystyrene is usually bonded by solvent cementing, it can be bonded with vinyl acetate/vinyl chloride solution adhesives, acrylics, polyurethanes, unsaturated polyesters, epoxies, urea-formaldehyde, rubber-base adhesives, polyamide (Versamid-base), polymethylmethacrylate, and cyanoacrylates. The adhesives should be medium-to-heavy viscosity and room-temperature and contact-pressure curing. An excellent source is a Monsanto Company technical information bulletin which recommends particular commercial adhesives for bonding polystyrene to a number of different surfaces. Adhesives are recommended in the fast-, medium-, and slow-setting ranges (10). 

Poly butylene Terephthalate (PBT) Commercial adhesives recommended include modified epoxies, cyanoacrylates, acrylics, polyurethanes, silicone, and polyesters. 

Polysulfone A number of adhesives have been found useful for joining polysufone to itself or to other materials. These include 3M Company s EC 880 solvent-base adhesive, EC 2216 room-temperaturecuring epoxy two-part paste, Bloomingdale Division, American Cyana-mid Company BR-92 modified epoxy with DICY curing agent, or curing agent "Z" (both spreadable pastes), vinyl-phenolics, epoxy-nylons, epoxies, polyimide, rubber-based adhesives, styrene polyesters, resorcinol-formaldehyde, polyurethanes, and cyanoacrylates. The EC 880, EC 2216, and the two BR-92 adhesives are recommended by the polysulfone manufacturer. Union Carbide (16) (17). 

Polyester Adhesives used include neoprene or nitrile-phenolic, epoxy, epoxy-polyamide, phenolic-epoxies, polyesters, modified acrylics, cyanoacrylates, polyurethanes, butyl rubber, polyisobutylene, neoprene, and polymethylmethacrylate (1). 

Phenolic Adhesives recommended are neoprene and urethane elastomer, epoxy and modified epoxy, phenolic-polyvinyl butyral, nitrile-phenolic, polyester, cyanoacrylates, polyurethanes, resorcinols, modified acrylics, polyvinyl acetate, and urea-formaldehyde (1). 

Urea-Formaldehyde Adhesives used are epoxies, nitrile-phenolics, phenol-formaldehyde, resorcinol-formaldehyde, furan, polyesters, butadiene-nitrile rubber, neoprene, cyanoacrylate, and phenolic-polyvinyl butyral (1). 

With the development of absorbable cyanoacrylate systems, the classification of synthetic, absorbable polymers into the traditional heterochain polymers (e.g., polyesters and polyanhydrides) and less-conventional homochain polymers (e.g., cyanoacrylate polymers) became inevitable. " Meanwhile, since ester-based systems are most important among both the heterochain-and homochain-type synthetic, absorbable polymers, they are given special attention in this chapter. 

Early demonstration that the absorption of poly(methoxypropyl cyanoacrylate) can be accelerated in the presence of hquid absorbable oxalate polymers led Shalaby to develop a new family of methoxypropyl cyanoacrylate (MFC)/polyester formulations as tissue adhesives with a broad range of properties. These formulations were tailored to produce absorbable tissue adhesives with a range of adhesive properties and compositionally controlled compliance depending on the type and content of the absorbable polyester component in the formulation. 

Shalaby, S. W., Polyester/Cyanoacrylate Tissue Adhesive Formulations, U.S. Patent (to Poly-Med, Inc.) 6,299,631, 2001. 

Based on the design criteria noted above, the evolution of the absorbable cyanoacrylate-based system commenced with methoxypropyl cyanoacrylate (MFC) and was followed by formulation of MFC with polyether oxalate or polyester carbonate. Figure 5.1 outlines a polymerization scheme and designation of the final polymer. Both V-100 and V-150 tissue adhesives contain the same components but in different proportions. 

Chemical properties Polyether-based materials have higher resistance to hydrolysis but are more vulnerable to photo-oxidation than polyester types. Good chemical resistance. Solvents cause reversible swelling but not solution. PUs can be adhered with polyurethanes, nitriles, epoxies and cyanoacrylates. 

Linear polyesters of lactides andglycolides, polyfalkyl cyanoacrylates), polyanhydrides, and poly-phosphazenes are some of the polymers commonly used in the development of polymeric particles. 

The use of synthetic adhesives in the past twenty-five years (1) has grown/ particularly the use of eight classes of polymers polyvinyl acetate/ polyolefins/ styrenic block copolymerS/ acrylicS/ cyanoacrylates/ anaerobicS/ polyurethanes/ and epoxy resins. Some of these polymers are Still in high demand as specialty adhesives (2). During the last several yearS/ however / other polymers have been added to this list/ e.g. / polyamides/ polyimideS/ and polyesters. Today/ synthetic adhesives account for 75% of the adhesives produced and 85% of the sales/ while the market share of natural products has steadily declined. 

Modified (or alloyed) phenolic Polyaromatics Polyester Polyurethane Anaerobic Cyanoacrylate Modified acrylic Neoprene (chloroprene) Nitriles (acrylonitrile-butadiene) Polysulfide Nitrile, vinyl, neoprene... 

Cellulose acetate natural rubber (latex), polyisobutylene rubber, neoprene rubber, polyvinyl acetate, ethylene vinyl acetate, polyacrylate (carboxylic), cyanoacrylate, polyamide (versamid), phenoxy, polyester + isocyanate, nitrile-phenolic, polyurethane, and resorcinol-formaldehyde. 

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