Abstract:
Disclosed is a method for controlling or reducing the amount of powder fines present in a polyethylene fluidized bed reactor. The method uses hydrocarbons that are inert with respect to the polymerization reaction, as well as using reactive olefins. The reduction of powder fines provides significant operating benefits in the fluid bed process, including reduced formation of powder agglomerates in the reactor and reduced fouling of equipment in the recycle gas stream.
Abstract:
Disclosed are orientable, heat setable, semi-crystalline copolyesters which have high glass transition temperatures. These copolyesters have high heat distortion temperatures along with excellent molding and film properties which makes them useful in packaging materials and molded parts. These copolyesters have repeat units from 100 mol % 1,4-cyclohexanedimethanol, 1-99 mol % terephthalic acid and 99-1 mol % naphthalene dicarboxylic acid.
Abstract:
This invention relates to a process for preparing amido ester compounds. The proces involves (I) forming a mixture in a reactor of a phenol derivative and an amido-carboxylic acid at a temperature which ensures at least partial solubility of the phenol derivative and the amido-carboxylic acid, and (II) adding a carboxylic anhydride incrementally to the mixture formed in Step (I) while distilling a by-product carboxylic acid from the reactor. The amido esters are useful as bleach activators.
Abstract:
The present invention discloses a polymerization system having at least two reaction chambers wherein vacuum is used to remove vapors therefrom comprising a single vacuum system for supplying vacuum in increasing amounts to successive reaction chambers. Also disclosed is a polymerization process having at least first and second reaction chambers in which the pressure is decreased successively from said first chamber to a final chamber, said process comprising the steps of: maintaining a vacuum in said final chamber by removing final chamber vapors therefrom via a final chamber ejector connected thereto by a vacuum line; directing discharge from said final chamber ejector into a first chamber precondenser to produce first chamber non-condensed materials and condensed first chamber ejector motive fluid; directing said first chamber ejector non-condensed materials from said first chamber precondenser to a second ejector connected thereto by a vacuum line; directing discharge from said second ejector into a second condenser to produce second condenser non-condensed materials and condensed second ejector motive fluid; wherein said second condenser is connected to a vacuum pump.
Abstract:
Provided are curable copolymers having 1,3-dioxolan-2-one-4-yl groups incorporated therein. The copolymers are useful as binders in coating compositions and can be cured with primary amine cross-linking compounds to form a continuous polyurethane coating.
Abstract:
The present invention relates to a process for preparing cellulose esters having a total DS/AGU of 0.1 to 3.0, said process consisting of contacting the following: (i) a cellulose material, (ii) a solubilizing amount of a solvent system comprising a carboxamide diluent or a urea-based diluent, (iii) an acylating reagent, and (iv) an insoluble sulfonic acid resin catalyst.
Abstract:
This invention relates to polymer compositions containing naphtalenedicarboxylic acid residues and having reduced fluorescence due to the presence of aromatic thioether compounds. More specifically, the polymer compositions contain poly(ethylene 2,6-naphthalene dicarboxylate) and 0.1 to 5 mole percent of an aromatic thioether compound. The polymers are useful for packaging applications where clarity and/or aesthetic appeal is important.
Abstract:
Disclosed are novel polyether compounds obtained by the reaction of polymerisation of 3,4-epoxy-1-butene in the presence of tetrahydrofuran, an acidic catalyst and a nucleophilic initiator compound. The polyether compounds comprise m units of residue (1), n units of residue (2), and p units of residue (3) wherein (i) residues (1), (2) and (3) have the structures (1), (2): -O-CH2-CH=CH-CH2-, and (3): -O-CH2-CH2-CH2-CH2-, (ii) the total value of m+n+p is 5 to 70; (iii) the value of n/(m+n+p) is in the range of 0.2 to 0.4, i.e., residue (2) constitutes from 20 to 40 mole percent of the total moles of residues (1), (2) and (3); and (iv) at least 98 percent of the terminal groups have the structure (4) or (5): HO-CH2-CH=CH-CH2-.
Abstract:
A process for the production of amorphous polyolefins is disclosed. The process entails contacting the olefin monomer, in an unreactive hydrocarbon solvent, with a catalyst in a recirculated, stirred reactor thereby producing amorphous polyolefin. The reactor is capable of recirculating contents that are very viscous.
Abstract:
This invention provides a method for imparting invisible markings for identification purposes to petroleum hydrocarbons by incorporating one or more infrared fluorescing compounds therein. Certain infrared fluorophores from the classes of squaraines (derived from squaric acid), phthalocyanines and naphthalocyanines are useful in providing invisibly marked petroleum hydrocarbons such as crude oil, lubricating oils, waxes, gas oil (furnace oil), diesel oil, kerosene and in particular gasoline. The near infrared fluorophores are added to the hydrocarbons at extremely low levels and are detected by exposing the marked hydrocarbon compositions to near infrared radiation having a wavelength in the 670-850 nm range and then detecting the emitted fluorescent light via near infrared light detection means.