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Research and Development
Nanocomposite Evaluation:
Melt Flow Properties
Melt flow properties are important for plastic processing. The dispersion of a Nanomer® in a polymer may change a plastic’s melt flow properties, necessitating changes in process parameters. Nanocor’s scientists measure nanocomposite melt flow properties by using Melt Flow Indexers as well as Rheometers to provide customers valuable processing guidelines. Accurate melt flow properties ensure success in nanocomposite processing, extrusion and fabrication.
Nanomer Dispersion
 Good Nanomer dispersion in a polymer resin is crucial to achieving performance. Optical and electronic microscopy technologies are the most common tools. Nanocor’s scientists utilize optical microscopes and proprietary techniques to investigate Nanomer dispersion in various forms of samples. Microscope images are also an important part of the quality control function for Nanomer concentrates in addition to nanocomposites themselves.
 Tensile Properties
Tensile properties are the mechanical responses of a test specimen under stretching conditions. Tensile properties are measured using an Instron Tensometer. Nanocor scientists typically measure tensile modulus, strength-at-yield, strength-at-break, strain-at-yield and strain-at-break. The Instron also has been used to measure film tear strength.
Impact Properties
Impact resistance quantifies brittleness in nanocomposites. Impact resistance (notched and un-notched) tests are conducted by using Izod Charpy method. Impact loss can be one disadvantage of nanocomposites. Using the proper Nanomer grade and appropriate processing conditions minimizes and in many cases eliminates impact loss.
 HDT (Heat Distortion Temperature)
HDT is the temperature at which a standard test bar deflects 0.010 inch under a load of either 66 or 264 psi. HDT provides usage/performance limitations for molded parts under elevated heat. This is a sought-after property in nanocomposites. Our capability here is important in determining performance in parts likely to be exposed to high heat.
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DMA (Dynamic Mechanical Analysis)
DMA can be simply described as applying an oscillating force to a specimen and analyzing the material’s response to the force under different temperatures. Nanocor scientists use DMA to obtain the storage modulus of a nanocomposite at elevated temperatures. DMA is particularly useful to obtain glass transition temperatures (Tg) of a thermoset nanocomposites, such as those using epoxy resin as the host matrix. Nanocomposite formation significantly increases the Tg of epoxies and extends their application temperatures.
 TMA (Thermal Mechanical Analysis)
TMA measures the thermal expansion of specimens at different temperatures. Nanocompositing reduces the thermal expansion coefficient for most of thermoplastic materials. Nanocomposites with reduced thermal expansion coefficients can be combined with other materials to form durable articles for many applications.
 DSC (Differential Scanning Calorimetry)
DSC measures the thermal response of a resin at different phase transition states, such as glass transition, crystallization and melting temperatures. This instrument is used to investigate the effects of Nanomer addition on a resin’s phase transitions. DSC has also been used to report resin crystallinity and ensure processing success. For example, the crystallinity of ImpermTM high barrier nanocomposite is critical to its performance in multilayer stretch blow molding of bottles.
 Mocon Permeameters
Nanocomposite technology significantly reduces the gas permeation of a polymer resin. In consumer packaging applications this enhancement extends product shelf life. Nanocor uses a variety of Mocon instruments to measure OTR (oxygen transmission rates) and WVTR (water vapor transmission rates) of nanocomposites under different relative humidity conditions.
 UL94 Flammability Testing
UL94, developed by Underwriters Laboratories, is the most widely used and most frequently cited flammability standards for plastic materials. The results are intended to serve as a preliminary indication of the material's suitability with respect to flammability for a particular application. The UL flammability tests include a standard burning protocol, applied to vertical or horizontal test samples, from which a general flammability rating is derived. Char layer formation has been recognized as a major contribution to reduced flammability nanocomposites. Nanocor's flammability chamber provides the capability for evaluating nanocomposites in combination with traditional flame retardant additives to enhance performance through synergism. Synergy of Nanomers with traditional fire retardants are reported in the Technical Paper Section.
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