Past projects

     The Advanced Polymer Laboratory is investigating the use of improved rigid polyurethane foams in Non-Lethal weapon applications.These applications includes but are not limited to sealing doors and windows thus either restricting personnel /troop movements within a building or confined area, denying access to areas/buildings/vehicles, and disabling mechanical equipment including weapon systems. In addition to counter-personnel applications, these foams can also be used as an adhesive for attaching equipment/devices/weapons to various hard surfaces. Polyurethane foam technology has been utilized successfully in the private sector for more than 50 years. This type of material is very versatile in terms of its chemistry and hence in terms of its technological applications. Properties such as degree of rigidity/flexibility, compression strength, open/closed cell structure and foam/gas content etc., can be essentially “dialed-in” by making predetermined adjustments to the material composition. The APL is developing closed cell, rigid PUR foams focusing on improving both their cure rate and their storage life for NLW applications. The storage issues are addressed by investigating the use of novel protected or “blocked” isocyanates and/or nanoencapsulated isocyanates. In order to achieve faster curing rates, we are studying the catalytic cycle of isocyanate condensation with active hydrogen compounds such as alcohols and then developing improved catalyst/substrate systems.

Liposome model for intranasal drug delivery

     Intranasal drug delivery has been a topic of increasing interest for a decade as a convenient and reliable method for the systemic administration of drugs. The low bioavailability of simple formulation of protein drugs, for example insulin, can be greatly improved by using permeation enhancers. We studied the effect of cyclopentadecanolide as a permeation enhancer in insulin release through membranes. Due to the complicity and availability of natural membranes, a model membrane using dipalmitoyl-phosphatidylcholine (DPPC) liposome was developed. Narrow size distribution DPPC liposomes were made by the extrusion technique. Fluorescence was used to detect fluorescein-tagged insulin at low concns. A method for insulin release through liposome was designed and the exptl. data accumulated show that cyclopentadecanolide does enhance the insulin release rate

• Polyethylene Nanocomposites

 5% MWCNT/PP Sample

•  New Generation retroreflective paints (NHDOT + 8 states)

•    This project dealt with a specific aspect of traffic paint, the improvement of retro-reflective bead retention. More specifically we studied the potential of polymethymethacrylate (PMMA) beads to act as a substitute for glass beads when their surface chemistry is modified to react (crosslink) with the binder chemistry. This project thus is a building block toward an ultimate goal of developing traffic paints with longer durability and sustained retroreflectivity. Within the scientific and technical scope of this project, performance at the time of application, whether initially high or low, is of minimal concern and focus and emphasis is on sustained performance. Retroreflectivity higher than 150 mCd/M2/Lx over a full season is generally considered desirable but does not constitute the objective of this project.This project involved two major phases: a laboratory development phase, where modified polymeric beads were produced, and a field test phase including limited comparison with conventional products. The development of the beads involved dispersion polymerization of acrylic copolymers on top of PMMA micro beads. The field testing of these beads was carried in two separate years, with 3 sites during a first year and a single site during a second year. The general results of year one are condensed here, and the comprehensive details of the field test of year two are described.

• Innovative Material Reducing Right Whale Entanglement (New England Consortium - NOAA)

       This project will show that innovative materials can be synthesized for the purpose of reducing Right Whale entanglement. The basic concept is to detach the line of floats from nets and other abandoned or lost fishing gear after a 15 days exposure to water. The development of an innovative composite tie made from advanced polymers that degrade after a controlled reaction with water is the core of this project. It has been generally recognized that innovative materials could provide solutions to some of the problems facing the fishing industry. Unfortunately limited resources have been invested due to the riskier nature of such research. This project will demonstrate that materials designed for the specific purpose of solving marine challenges have great potentials. We propose to revisit this problem by bringing advanced concepts of polymeric materials design. I will produce a composite tie that decomposes after continuous immersion in sea water at 12°C for 15 days, but with very limited loss of strength before that time period, and recovery of mechanical properties for immersions shorter than 15 days. The composite tie would be the link between the floats and the netting. Upon severance of the float, the weighted net would sink to the seafloor.Such a material would have tremendous application in fishing gear design and usage.Lost gillnet would stop "ghostfishing" after a short period.Entangled Right whales and other marine animals, would be freed from fishing lines and nets in a short time period. It is important to note that from design it is expected that the material would “recover” from limited water immersion and no replacement of the tie would be necessary unless a full continuous 15 day water immersion was to occur. If successful, such material realistically would have to be replaced annually.

     A new generation of anti-fouling agent has found its way to the market, based on an organic molecule 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, or Sea-nine 211® commercialized by Rohm and Hass. This molecule has the property to inhibit the development of algae’s and crustaceans. A parallel route to fouling control is the advantageous use of high energy flat polymeric surfaces. Materials such as polydimethyl siloxane, known as silicones, can offer extremely smooth surfaces with very limited chemical anchoring opportunities for marine organisms. Upon mild shear, such as water displacements of 5-8 knots, all recently implanted cellular materials are sheared (cleaved) off the surface. A solution to the optic fouling problem may be found in combining these two fundamental approaches, creating a transparent silicone formulation that contains the organic antifouling agent.  Silicones are strong, flexible, chemically very stable and extremely water resistant. This combination of properties is the reason of their broad application in aqueous environment (window sealants, gaskets, molds…).