摘要:
Disclosed is a method of increasing the yield of 2,6-NDA which comprises: a) Dissolving a disproportionation reaction product containing a dialkali salt of 2,6-NDA in water and filtering off insoluble matter from the resulting solution; b) Precipitating the monoalkali salt of 2,6-NDA (KHNDA) with CO2; c) Suspending said monoalkali salt in water in a weight ratio higher than 8:1, water: monosalt; and d) Heating at a temperature above 100° C. and at a pressure above 100 psig. The improvements in yield are from about 20% to as high as 45%.
摘要:
Polymer compositions comprising .alpha.-olefin polymers and a minor proportion of synthetic basic zeolite are stabilized against the harmful effects of corrosion of metal surfaces when processed through mechanical equipment such as molds and extruders where the composition normally contacts metal surfaces.
摘要:
A lightweight absorbent foam is produced using a high internal phase emulsion (HIPE), the production of which incorporates the use of capillary viscosity measurements as an in-line diagnostic for HIPE quality. The in-line diagnostics yield measurements of viscosity slope and amplitude. These measurements offer several advantages for monitoring emulsion quality, including stable high resolution measurement of hardware-independent parameters of the whole flow, without the need for sampling.
摘要:
A process for the removal of soluble selenium from aqueous media comprising contacting the aqueous media with a porous support material having exchanged thereon metal ions selected from transition metal ions, alkali earth metal ions and mixtures thereof.
摘要:
In a process for the preparation of a low density porous crosslinked polymeric material by polymerizing a water-in-oil high internal phase emulsion, curing time of the monomers in the emulsion can be reduced without adversely affecting polymer properties or substantially affecting the emulsion by carrying out the curing in multiple-stages. The emulsion is first pre-cured at a temperature less than about 65.degree. C. until the emulsion reaches a Rheometrics dynamic shear modulus of at least about 500 and subsequently curing at a temperature above about 70.degree. C.
摘要:
In a process for the preparation of a low density porous crosslinked polymeric material by polymerizing a water-in-oil high internal phase emulsion, curing time of the monomers in the emulsion can be reduced without adversely affecting polymer properties or substantially affecting the emulsion by carrying out the curing in multiple-stages. The emulsion is first pre-cured at a temperature less than about 65.degree. C. until the emulsion reaches a Rheometrics dymanic shear modulus of at least about 500 and subsequently curing at a temperature above about 70.degree. C.
摘要:
This invention relates to basic compositions comprising a zeolite and an alkaline earth metal compound wherein the sum of the amount of the alkaline earth metal in the compound plus any metal cation exchanged into the zeolite is in excess of that required to provide a fully metal cation-exchanged zeolite. This invention further relates to methods for preparing the instant compositions. In a preferred embodiment the instant compositions are prepared by impregnating a zeolite with a solution of an alkaline earth metal salt wherein said alkaline earth metal impregnated in the zeolite is in excess of that required to provide a fully metal cation-exchanged zeolite, precipitating out an insoluble alkaline earth metal compound within the zeolite by contact with a precipitation agent, and/or drying the resultant impregnated/(precipitated) material and then calcining the resultant composition.
摘要:
The present invention provides an curable composition comprising (1) at least one epoxy compound containing at least one vicinal-epoxy groups, (2) a miscible amount of at least one ethylenically unsaturated monomer and (3) a curing amount of at least one catalyst selected from lithium or Group II metal salts of a non-nucleophilic acid.