New Mexico Tech Research Foundation

John P Heller

Zhongming Chen

Dileep K Dandge

James V McLemore

Pratap Gullapalli

A one-pot method of preparing sulfonic acid-terminated polyisobutylene by sulfonation with acetyl sulfate of living polyisobutylene in a single step. The method permits preparation of sulfonated telechelic polyisobutylenes (STPs) by 'inifer' initiated carbocationic polymerization of isobutylene with Lewis acid to form a polymer, followed by the addition in the same reaction vessel of acetyl sulfate at the polymerization temperature or the decomposition temperature of the complex.

End-quenching the living polymerization of isobutylene with acetyl

The disclosure relates to an apparatus and method for determining the permeability and the porosity of small sections at and just below the surface of a slabbed sample of porous rock or other material. The measurement is performed by forcing air or other gas through a central passageway of a deformable (e.g. rubber) probe tip pressed against the surface of the sample to be tested. Permeability of the matter directly under the probe tip is computed from the ratio of flow rate into the sample to the pressure drop between the gas in the probe-tip and the ambient atmosphere. A preferred and an alternative means for measuring flow rate are disclosed involving the use of an optical interferometer to detect displacement of a bellows chamber. The apparatus of the invention includes a fact-acting valve such that immediately after calculation of the permeability of the sample under defined conditions, a precise value of the porosity of the same sample may be computed from the transient pressure change that is observed after cutting off air flow into the sample from the probe.

Miniporopermeameter

Solvent-type flooding fluids comprising light hydrocarbons in the range of ethane to hexane (and mixtures thereof) are used to displace crude oil in formations having temperatures of about 20 degrees to about 150 degrees Centigrade and pressures above about 650 psi, the light hydrocarbons having dissolved therein from about 0.05% to about 3% of an organotin compound of the formula R.sub.3 SnF where each R is independently an alkyl, aryl or alkyaryl group from 3 to 12 carbon atoms. Under the pressures and temperatures described, the organotin compounds become pentacoordinated and linked through the electronegative bridges, forming polymers within the light hydrocarbon flooding media to render them highly viscous. Under ambient conditions, the viscosity control agents will not readily be produced from the formation with either crude oil or water, since they are insoluble in the former and only sparingly soluble in the latter.

Growing community of inventors

Socorro, NM, United States of America

John P Heller