Infusion Processes

1.0 – Infusion Process Profile
Integument Technologies, Inc. (ITI) has developed a new patented infusion process that allows metals, metal oxides, and organic precursors to form interpenetrating networks (IPN) within the internal structure of a polymer. These IPNs are generated by exposing the polymer to a three-step procedure:

  1. Evacuation of ambient air from the naturally free space within the polymer.
  2. Infusion into the polymer free space with the desired volatilized precursor.
  3. Treatment of the infused polymer to stabilize and control particle size of the IPN.

The infusion process can create original composite materials from a virtually unlimited number of precursor-polymer combinations.

The infusion process provides many advantages in the production of polymer composites including the ability to:

ITI’s infusion technology is used to fabricate a variety of novel polymer composites with unique mechanical, optical, electrical, and chemical properties. Some examples include:

In addition, this technology can be combined with ITI’s polymer surface modification treatment system to create original materials for use in such fields as coatings, catalysis, filtration and semiconductor processing.

2. 0 – Infusion Technology
ITI’s patented infusion technology can be used to modify both bulb and surface properties of polymers. The process is capable of introducing nanoparticle sized organic and/or inorganic species into the bulk of polymeric film, sheet, resin, powder and finished products.

ITI’s infusion process is unique in that we do not blend materials into a polymer melt. Neither do we utilize high pressures, temperatures, or chemicals to force additives into a polymer. Instead, ITI infuses volatilized precursors under vacuum directly into polymeric materials. After infusion, the infused materials form controlled, concentrated interpenetrating networks that are homogeneously dispersed inside the polymer. These networks are not in the pores, if they are present, of the newly created composite. They instead are tightly locked in the non-crystalline free spaces of the polymer producing a true nano-dispersed highly durable composite material useful in numerous applications.

2.1 – Infusion Composites
Integument Technologies has developed a new class of patented composites by permanently infusing metals, metal oxides, and volatile organic precursors into virtually any amorphous polymer. These precursors are treated after infusion to create interpenetrating networks (IPN) in the free volume of the composite. The particle sizes of these networks may be controlled depending on the post-infusion treatment employed.

Currently, metal-polymer composites are made either by 1) melting the polymer phase and then adding the inorganic and organic phases into the molten polymer, 2) by dissolving the polymer and inorganic material together into a common solvent, or by 3) hydrolyzing inorganic precursors and polymer in a common solvent. By contrast, ITI’s straightforward infusion process offers a significant improvement over current composite manufacturing methods.

Infusion is clean, fast, economical and most importantly produces finely controlled homogenous composite materials.

The table below shows the advantages of infusion in composite development.

Infusion Mixing
Homogeneous IPN distribution. Separate organic, inorganic phases within bulk polymer.
Bulk properties of starting polymer may be either altered or retained in the infused composite. Solvents frequently alter polymer physical properties.
IPN’s fixed permanently within target polymer with controlled particle sizes. Frequent migration and leaching of precursors from polymer.
Predictable composite mechanical properties. More uncertainty in physical attributes in resulting composite.
Electronic, optical and catalytic properties may be retained. Variation in electronic, optical, catalytic properties.
Easily scaled-up to adapt to production environment. Production scale-up more problematic.

2.2 – Composite Properties

Polymer Dyeing

Several high commodity polymers (e.g., polypropylene, polyesters, etc.) suffer from the lack of techniques available that allows these materials to accept and permanently hold a dye. For example, polypropylene requires precompounding of the resin with a pigments that can be compounded reduces the film or fabric. The list of pigments that can be compounded reduces the available range of colors to these materials. Dyes on the other hand are available throughout the full range of the color spectrum.

ITI has demonstrated that by infusing polypropylene or polyester fabrics with materials that possess ligands capable of bonding dye molecules within the free volume of these materials, one can easily (and less expensively than compounding pigments) fabricate dye colored materials not available before. This method has been demonstrated to be capable of permanently binding acidic or electrostatic dyes directly from a solution into polypropylene and polyester fabrics. Alternatively we have infused SiCI4 or tetraethoxy silane into polypropylene that subsequently form SiO2 macromolecular units that are capable of permanently binding basic or electrostatic dyes within the Polypropylene matrix. ITI has also infused several materials that can form permanent covalent bonds to a wide variety of dyes or optical materials.

UV Shielding

Ti02 infusion (among other compounds) can be used to absorb UV (B). Additionally via subsequent:

  1. Doping with pentavalent species such as Vanadium or Phosphorous.
  2. Ligation to ethylenediamine or diethyletriamine.
  3. The formation of Titanium/Zinc Oxide hybrid – one can further tune the absorbance in order to block UV (A) without significantly adding color to the film. I.e.,in order to absorb or block UV(A) one typically needs to add a colored absorber that lowers optical clarity in the visible region of the light spectrum.

Enhanced Gas Permeation

Gas permeation through polymer materials is an important issue related to many industrial applications. Via ITI’s infusion process, we have demonstrated the ability to change gas permeation rates through several materials including the ability to selectively enhance transport of a desired gas while reducing the permeation or transport of undesired gases.

Anti-Microbial Polymers

Similar to the above infusion methods that can be used to permanently couple dye materials into polymer matrices, other materials can be infused that possess ligands that have desired chelating qualities. For example many materials can be readily infused that have formation constants (Kf) that are useful for chelating various materials including anti-microbials (e.g., Ag , Zn, or Cu) in such a manner that controlled release can be effected. Using this method we have demonstrated on a polypropylene fabric the ability to controllable release Ag ion in order to achieve a 100% bacterial kill rate even after many industrial wash cycles. Note that after the chelated agent is finally depleted the material can be readily recharged via simple solution exposure.

Interfacial Adhesion Properties

The infusion of functionalized organo-silanes can be effected in such a manner as to produce novel surface properties that are made permanent by interlocking the subsequent siloxane into the materials’ bulk via the formation of interpenetrating networks. Depending on the initial choice of organosilane, one can fabricate (on almost any polymer material) both enhanced and specific bonding properties (useful for obtaining outstanding adhesion to polyolefins or fluoropolymers) or: alternatively, enhanced non-stick (water and stain repellent) surface properties.

3.0 – Licensing and Alliance Opportunities
Licensing and alliance opportunities are available. ITI offers world-class intellectual property, custom plasma equipment design and construction and state-of-the-art fluoropolymer technologies.