Abstract:
An autonomic self-indicating material is provided, the material comprising a polymer composition or a composite material embedded with a microcapsule or a vascular structure comprising an aggregation-induced emission (AIE) luminogen. Upon mechanical damage to the material, the luminogen is released and aggregates, leading to fluorescence.
Abstract:
A multifunctional syntactic foam including a matrix material and hollow particles, where a first and second material property of the syntactic foam are tailored on the basis of the wall thickness and volume fraction of the hollow particles.
Abstract:
Improved methods of detecting thermal exposure are provided herein. The provided methods utilize initially dormant luminescent probes incorporated into a matrix to form a composite. When exposed to heat over a period of time, the luminescent probes are “activated” through a molecular transformation initiated by thermal energy. The activated probes exhibit a luminescent profile based on the extent of thermal exposure, thereby providing an indicator of the thermal exposure experienced by the matrix. When the composite is used to produce a structural component of a vehicle (e.g., an aircraft), the methods provide a convenient, large-area indicator of thermal damage experienced by the structural component.
Abstract:
A composite elastomeric flexible element has an elastomer layer between rigid members. When subjected to loads, and as time goes by, the elastomer layer will undergo damage in the form of micro-voids and polymer chain scission. The time it takes the damage to reach a predetermined, but safe state is a known function of several parameters such as loading rate and load magnitude, time at load, temperature and frequency. The damage decreases the electrical permittivity of the elastomer and changes the electrical conductance of the elastomer if the elastomer is in the environment of an electrically conductive fluid or when the elastomer includes conductive filler. The health of the flexible element is monitored by measuring the electrical impedance of the elastomer layer, computing an indication of health from the electrical impedance and trend data for the elastomer layer, and reporting the indication of health to a human administrator.
Abstract:
A method for examining wear of a connector contact using atom transfer radical polymerization. Metals in the connector contact are involved in atom transfer radical polymerization. In the method, polymers are formed via atom transfer radical polymerization. An average molecular weight and a polydispersity index of the polymers are determined. The exposure of underlying metal layers of the connector contact is determined based on the average molecular weight and atom transfer radical polymerization.
Abstract:
A measurement system includes semiconductor light sources generating an input beam, optical amplifiers receiving the input beam and delivering an intermediate beam, and fused silica fibers with core diameters less than 400 microns receiving and delivering the intermediate beam to the fibers forming a first optical beam. A nonlinear element receives the first optical beam and broadens the spectrum to at least 10 nm through a nonlinear effect to form the output optical beam which includes a near-infrared wavelength of 700-2500 nm. A measurement apparatus is configured to receive the output optical beam and deliver it to a sample to generate a spectroscopy output beam. A receiver receives the spectroscopy output beam having a bandwidth of at least 10 nm and processes the beam to generate an output signal, wherein the light source and the receiver are remote from the sample, and wherein the sample comprises plastics or food industry goods.
Abstract:
A method of determining degradation of a thermoplastic when exposed to light and heat includes illuminating the thermoplastic with a desired wavelength of light at a desired irradiance while maintaining the ambient air surrounding the thermoplastic at a desired temperature. The method is useful to measure the discoloration rate of transparent, translucent and opaque thermoplastics such as polycarbonates, the discoloration rate being determined by transmission or reflectance spectra of transmitted or reflected white light through or from the thermoplastic.
Abstract:
A device for ascertaining the corrosiveness of a plastic melt, including a housing having a cavity to be filled with plastic melt; a first electrode made of a first material and a second electrode made of a second material, the first electrode and the second electrode each having a contact surface toward the cavity, the standard potential of the first material being higher than that of the second material, and the first electrode and second electrode additionally being connectable to each other via a measuring element for determining an electric current and/or an electric voltage between the contact surfaces.
Abstract:
A curable composition having a polythiol; at least one unsaturated compound comprising two or more carbon-carbon double bonds, carbon-carbon triple bonds, or a combination thereof; and a dye compound represented by formula: A crosslinked composition prepared from the curable composition, a method for indicating curing in a curable composition, and a method of stabilizing a curable composition comprising a polythiol and at least one unsaturated compound comprising two or more carbon-carbon double bonds, carbon-carbon triple bonds, or a combination thereof are also disclosed.
Abstract:
Devices and methods for immobilizing micrometer sized liquid domains onto a chemically functionalized substrate surface are disclosed. A multifunctional polymer is adsorbed at the surface interface of the liquid microdomains, and the liquid microdomains are immobilized by covalent bonding or non-covalent forces such as electrostatic attraction between the adsorbed multifunctional polymer and the functionalized substrate surface.