This disclosure relates to polymer compositions comprising blends of polyesters and phosphonate oligomers or polymers as well as methods of making them and articles of manufacture made from such blends.

A mixture of poly(alkylene phosphates) having reduced hygroscopicity, includes at least three poly(alkylene phosphates) of the formula

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wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4, mutually independently, are an n-butyl moiety or a 2-methylpropyl moiety, and is usable for flame retardants, such as a flame retardant in polyurethanes.

The present invention relates to a thermosetting resin composition, which comprises: (A) cyanate ester compound and/or cyanate ester prepolymer; and (B) polyphosphonate ester and/or phosphonate-carbonate copolymer. The thermosetting resin composition provided by the present invention has low dielectric constant and dielectric loss tangent. The prepreg and copper clad laminate made from the above-mentioned thermosetting resin composition have excellent dielectric properties and wet-heat resistance, UL94 V-0 flame resistance, and good processability.

This disclosure provides for new polyisocyanurate (PIR) foams that exhibit improved flame retardant properties and thermal barrier properties, and which can pass certain thermal barrier tests in the absence of a protective covering such as specified in the thermal barriers codes. In an aspect, it has been unexpectedly discovered that when a relatively high viscosity and high functionality polyisocyanate is used with a high aromatic content polyester polyol and an HFO and/or HCFO blowing agent, and a flame retardant compound, unexpectedly good flame retardant polyisocyanurate foams can be generated, for example, when a high A-side:B-side volume ratio (v:v) and a relatively high Isocyanate Index (ISO Index) are used in the process.

A flame retardant polyamide composite that includes a polyamide and a synergist, where the synergist includes a polymer having a backbone and a side unit of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide bonded thereto. Furthermore, the backbone of the polymer includes at least one heterocyclic moiety. Additionally, the flame retardant polyamide composite includes a flame retardant agent, where the synergist and the flame retardant agent are present in an amount ranging from more than 0 to 10 wt %. Furthermore, a method of forming the flame retardant polyamide composite includes cryogenic milling a synergist, mixing the synergist with a flame retardant agent to obtain a mixture, and compounding the mixture with a polyamide to obtain the flame retardant polyamide composite.

A resin composition includes a vinyl group-containing resin and a phosphorus-containing copolymer, wherein the phosphorus-containing copolymer is prepared from a mixture subjected to a copolymerization reaction, and the mixture includes a vinyl group-containing benzocyclobutene of Formula (1) and a phosphorus-containing compound of Formula (2). The resin composition may be used to make various articles, including a resin film, a prepreg, a laminate or a printed circuit board, and one or more of the properties can be improved, including dissipation factor, copper foil peeling strength, flame resistance and X-axis coefficient of thermal expansion.

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Methods and compositions for processing polymers with fluorine-free polymer processing aids (PPAs) are described. The methods can include extruding a polymer composition, optionally with a masterbatch, wherein the polymer composition and/or the masterbatch comprises a fluorine-free PPA to make a polymeric film. The PPA comprises a mixture of one or more polyamides and one or more polyphosphites.