Other

Center for Innovative Technology

College of William and Mary

Kranbuehl, David E.

David E Kranbuehl

Robert L Fox

John-Andrew S Hocker

Hannes C Schniepp

Minzhen Cai

Sarah Cotts

Arthur Jaeton Glover

The heat of fusion is used as a measure of the brittleness of a semicrystalline polyamide part. Parts made of or which include semicrystalline polyamides can be replaced or be identified for replacement when they are or will become brittle based on periodic heat of fusion measurements.

Ductile-brittle transition of poly(amide) as determined by a heat of fusion-crystallinity number

The molecular weight distribution in a polymer sample can be used as a measure for when parts need to be replaced, and can be tracked over time to allow for predicting when parts need to be replaced and/or identifying the type of aging taking place in the polymer part. Molecular weight distribution determination has particular application in determining the replacement time and or aging parameters in polyamide (e.g., formed from 11-aminoundecanoic acid or formed from 12 aminododecanoic acid) polyvinyldiflouride, and polyethyelene pipe liners used in, for example, offshore oil and gas production and fuel transport operations.

Multi point method and apparatus for monitoring the aging and changes in corresponding tensile performance properties of a polymer

In one embodiment, a method for producing a graphene-containing composition is provided, the method comprising: (i) mixing a graphene oxide with a medium to form a mixture; and (ii) heating the mixture to a temperature above about 40&#xb0; C., whereby a graphene-containing composition is formed from the mixture. Composites of polymers with disperse functionalized graphene sheets and the applications thereof are also described.

Method for making polymer composites containing graphene sheets

A method involving the use and creation of pre-aged witness coupons which characterizes and monitors the rate and extent of chemical and physical aging of the polymer in the structure during use in the field is described.

Method to predict the end-point, replacement time and to monitor changes in that time using pre aged witness coupons

Method to predict the end-point, replacement time and to monitor changes in that time by using pre aged witness coupons

The molecular weight of NYLON 11.RTM. (a polyamide made from aminoundecanoic acid) has been found to be a reliable indicator of the mechanical properties and remaining useful life of parts made therefrom. By periodically monitoring the molecular weight, and comparing the measured molecular weight to a standard curve or table, the expected useful life remaining, rate of deterioration, time of part replacement, and mechanical properties of a part can be determined. The molecular weight may advantageously be determined using witness coupons placed in close proximity to the part such that they are exposed to the same processing and environmental conditions as the part. These witness coupons can advantageously be retrieved at the required time period using a spooled piece of pipe or the like. Alternatively, the molecular weight may advantageously be determined from core samples taken from the part being monitored, during use in the field, on a periodic basis. In addition, the molecular weight might also be inferred from a sample held in a laboratory which is exposed to substantially the same environmental conditions as the part. The molecular weight measurements can be made using standard techniques and equipment such as a viscometer, gel permeation equipment, or light scattering equipments.

Method and apparatus for monitoring nylon 11 made from polyamide plastic

A dosimeter with reproducible changes in .epsilon.', .epsilon.'', or their equivalent two parameter circuit representations, under a given treatment regime that correlate directly with changes in physical attributes of a material or fluid, such as strength, modulus or viscosity, is used to monitor the deterioration of the physical attributes of the material or fluid.

Dosimeter for monitoring the condition of polymeric materials and

An L-C circuit (tank circuit) is located in close proximity to polymer impregnated composite material layers during the fabrication process. Applicant has determined that the resonant frequency of the tank circuit and the shape of the frequency absorption curve vary as a function of the fiber density of polymer impregnated composite material. The frequency of the input to the tank circuit is periodically swept through a range of frequencies, and the tank circuit impedance is measured to determine the resonant frequency and shape of the frequency absorption curve.

Tank circuit sensor for monitoring resin graphite composite fiber

A dielectric probe for use with conventional frequency and time domain impedance analyzers comprises two chemically resistant electrodes deposited in an interdigitated pectinate configuration on particular non-conductive substrates, the spaces between the digits thereof being no greater than about 0.01 inch; methods and apparatus for monitoring and/or controlling chemical reactions, particularly polymerization reactions, in contact therewith, wherein the complex permittivity may be calculated over a wide range of frequencies and temperatures.

Growing community of inventors

Williamsburg, VA, United States of America

David E Kranbuehl