Cyanate plastic

PUR are a broad class of highly cross-linked plastics prepared by multiple additions of poly-functional hydroxyl or amino compounds. Typical reactants are polyisocyanates [toluene diisocyanate (TDI)] and polyhydroxyl molecules such as polyols, glycols, polyesters, and polyethers. The cyanate group can also combine with water this reaction is the basis for hardening of the one-part foam formulations. 

Sample No. Prepolymer Mol. Wt. Diiso- cyanate Cross- linking Agent Plasticizer (%)... 

It was first synthesized by Friedrich Wohler in 1828 by evaporating a solution of ammonium cyanate. Urea is found in small amounts in the blood of mammals. Its principal industrial usage is in the manufacture of plastics (specifically, urea-formaldehyde resin) and is also a component of many fertilisers, providing a nitrogen source for plants. 

Chien lY, Nguyen MN. Pursuing the Perfect Paste A Novel Cyanate Ester Die Attach Adhesive for Plastic Packaging. Solid State Technol. Nov. 1994. 

The basic chemical reactions, used to synthesize monomer and polymer resins and the chemistry involved in the use of curing agents to polymerize the resins, have been extensively studied and are well documented. This section serves as a summary only of those polymers that are primarily used in adhesives formulations for electronic applications. Among these polymers are the epoxies, silicones, polyurethanes, polyimides, acrylates, cyanate esters, and cyclo-olefins. Further technical detail for these polymers maybe acquired through literature searches in the transactions of the American Chemical Society (Polymer Group), Society of Plastics Engineers (SPE), and the Society for the Advancement of Materials and Process Engineers (SAMPE). 

Ablefill UF 8807/ Ablestik Labs. Moisture-resistant cyanate ester (silica filled) 10 Plastic, ceramic, andPWB laminates Dispense, capillary underfill CSP or BGA packages and high-density interconnect substrates... 

Ablefill UF8806LP/ Ablestik Labs. Moisture-resistant cyanate ester (siUca filled) 1-3 Plastic, ceramic, FR-4, polyimide, and Rigid BT Dispense (22-25 gauge needle), capillary underfill Alpha-emission sensitive, fine-pitch appUcations... 

Molded plastic, smaller die sizes (PDIP, QFP) High strength, low-temperatiue processing (<250°C), moisture resistance Silver-filled epoxy, modified cyanate-ester and thermoplastic/ thermoset blends... 

VLSIC in TQFP/thin outline plastic Low modulus of elasticity (MOL), low-moisture absorption Epoxy, cyanate-ester blends... 

This is a low viscosity liquid, which dissolves many amorphous plastic resins, with high TgS enabling their ready incorporation into hot melt systems. It is compatible with cyanate ester prepolymers, epoxy resins and bismaleimides. 

There are numerous industry standard laminate constructions, and one of the leading sets of standards is that established by the National Electrical Manufacturers Association (NEMA). Some of the most commonly used resins are epoxies, polyesters, polyimides, cyanate esters, and phenohcs. Some of the most common reinforcements are paper, glass fiber, glass fabric, and certain plastic fibers and fabrics. 

As a family of resins originally developed in the early twentieth century, the nature and potential of phenolic resins have been explored thoroughly to produce an extensive body of technical literature (1-9). A symposium sponsored by the American Chemical Society commemorated 75 years of phenolic resin chemistry in 1983 (10), and in 1987 the Phenolic Molding Division of the Society of the Plastics Industry (SPI) sponsored a conference on phenolics in the twenty-first century (1). Exciting new developments continue as new systems are developed for carbon-carbon composites, aramid honeycombs, and new derivative chemistries such as cyanate esters and benzoxazines. New U.S. patents with phenolic resins in the claims are growing at about 150 patents per year. 

Phosgene is an intermediate in the chemical industry for the production of di-iso cyanates, polycarbonate plastics, chloroformic esters, carbonate esters, dyes [13] etc. Phosgene is produced from carbon monoxide and chlorine... 

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