Abstract: Disclosed herein are processes comprising the steps of providing a porous mat comprising carbon nanotubes having an average longest dimension in the range of 1 micron to 1000 microns, wherein at least a portion of the carbon nanotubes are entangled; contacting the mat with one or more condensation polymer precursors, and optionally a catalyst; polymerizing the one or more polymer precursors in the presence of the mat at a temperature in the range of about 180° C. to about 360° C. to form a nonporous carbon nanotube-polymer composite comprising a mat of carbon nanotubes embedded in a condensation polymer produced from the polymer precursors, wherein the carbon nanotubes are present in the composite in an amount ranging from about 15 weight percent to about 80 weight percent, based on the weight of the carbon nanotubes and the condensation polymer; and optionally, curing the carbon nanotube-polymer composite.

Abstract: Disclosed herein are ballistic resistant articles comprising one or more woven fabric layers woven from yarns having a tenacity of at least 7.3 grams per dtex and a modulus of at least 100 grams per dtex and one or more sheet layers comprising a carbon nanotube-polymer composite, the composite comprising randomly oriented carbon nanotubes embedded in a condensation polymer.

Abstract: Disclosed herein are processes comprising the steps of providing a porous mat comprising carbon nanotubes having an average longest dimension in the range of 1 micron to 1000 microns, wherein at least a portion of the carbon nanotubes are entangled; contacting the mat with one or more condensation polymer precursors, and optionally a catalyst; polymerizing the one or more polymer precursors in the presence of the mat at a temperature in the range of about 180° C. to about 360° C. to form a nonporous carbon nanotube-polymer composite comprising a mat of carbon nanotubes embedded in a condensation polymer produced from the polymer precursors, wherein the carbon nanotubes are present in the composite in an amount ranging from about 15 weight percent to about 80 weight percent, based on the weight of the carbon nanotubes and the condensation polymer; and optionally, curing the carbon nanotube-polymer composite.

Abstract: Methods and compositions for improving certain physical properties of polyesters are provided. The compositions are based on poly(trimethylene ether)glycol, and can improve properties such as toughness and flexibility in polyesters, providing a balance of desired properties.

Abstract: The invention relates to methods and systems for the use of an oligomer recyclate from a depolymerization product stream. The oligomer byproduct of a polyester depolymerization reaction can be used as a reactant in the formation of a polyester. For example, linear oligomer byproduct can be used as a reactant in a solution polymerization to form a low-acid polyalkylene terephthalate.

Abstract: The invention relates to methods and systems for selective removal of catalyst residue from a depolymerization product stream without a water quench, as well as methods and systems for subsequent recovery of residual linear oligomer. The substantially metal-free and substantially water-free residual oligomer byproduct can then be advantageously used as recyclate in a process for preparing MPO. For example, the residual oligomer recyclate can be used as a reactant in the polymerization and subsequent depolymerization (cyclization) of low-acid polyester to form MPO.

Abstract: The invention relates to a method for producing low-acid polyalkylene terephthalate from which MPO can be advantageously manufactured. In certain embodiments, the acid content of commercially available polybutylene terephthalate (PBT) is reduced by adding a small amount of 1,4-butane diol (BDO) to a solution of the commercially available PBT in refluxing ortho-dichlorobenzene (oDCB) solvent.

Abstract: The invention relates to a method for producing low-acid polyalkylene terephthalate from which MPO can be advantageously manufactured. In certain embodiments, low-acid polybutylene terephthalate (PBT) is prepared by reacting low molecular weight, diol-stopped PBT pre-polymer with a linear oligomer recyclate in refluxing ortho-dichlorobenzene (oDCB) solvent. The linear oligomer recyclate may be a by-product of the depolymerization/cyclization of the low-acid PBT, thereby synergistically increasing overall conversion of reactants to the MPO product, cyclic polybutylene terephthalate (cPBT).