Abstract:
A method for producing expanded thermoplastic polymeric (eTP) material and tuning the density of the eTP during the process of producing said eTP wherein the density of the eTP material can be decreased by increasing the partial pressure of the at least one gas which is soluble in the TP material and/or by increasing the total pressure during the charging step.
Abstract:
A method for producing environmentally friendly, mono-extruded hemp composite board (EHB) is provided. By using hemp fiber and hemp hurd in combination with virgin and/or recycled binders, the system and method may be used to create preferable substitutes for traditional construction boards. The method generally comprises steps of processing hemp hurd/fiber and injecting said hemp hurd/fiber into an extruder along with a binder. Waste products from other production streams may be added as well to reduce waste/cost of said production streams. The resulting EHB is structurally superior to traditional construction boards largely due to the structural characteristics of dispersed hemp hurd and hemp fiber, their complete encapsulation in a binder material, and their lower hygroscopic properties. Additionally, since the EHB is created using an extruder, a downstream extrusion arrangement may be used to mold the EHB into shapes that are difficult to achieve with traditional construction boards.
Abstract:
Disclosed, among other things, are ways to manufacture reduced density thermoplastics using rapid solid-state foaming and machines useful for the saturation of plastic. In one embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity. In another embodiment, a foaming process may produce layered structures in reduced density plastics with or without integral skins. In another embodiment, a foaming process may produce deep draw structures in reduced density plastics with or without integral skins. In yet another embodiment, a foaming process may utilize additives, blends, or fillers, for example. In yet another embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity.
Abstract:
Ultra-stable aqueous foam comprises hydrophobic silica particles residing within bubbles in an aqueous solution of a hydrophilic polymer, a protein, or aqueous dispersible colloidal particles. The combination of the hydrophobic and hydrophilic components stabilizes the foam interfaces to result in long term stability of the foam. The foams can be crosslinked to stable monolithic foams and used for structural foams, coatings, and thermal insulating for construction.
Abstract:
A process for making a foam composition, the process comprising the steps of: (A) Forming a mixture comprising high density polyethylene (HDPE), low density polyethylene (LDPE) and a peroxide; and (B) Contacting the mixture of (A) with carbon dioxide (CO2) at a pressure greater than or equal to 15 megaPascals (MPa). In one embodiment the peroxide is DTAP. In one embodiment the mixture of (A) further comprises a CO2-philic compound such as PDMS.
Abstract:
A thermoplastic elastomer foam is made by incorporating a gaseous or supercritical blowing agent under pressure into a molten thermoplastic elastomer comprising polymeric polymeric crystalline domains, then releasing the pressure to foam the thermoplastic elastomer.
Abstract:
A method of making a foamed article comprises (a) milling a block or sheet of thermoplastic polymer to form a precursor; (b) crosslinking the thermoplastic polymer; (c) heating the precursor to a first temperature to soften the thermoplastic polymer; (d) infusing the thermoplastic polymer with at least one inert gas at a first pressure that is sufficient to cause the at least one inert gas to permeate into the softened thermoplastic polymer; and (e) while the thermoplastic polymer is softened, reducing the pressure to a second pressure below the first pressure to at least partially foam the precursor into a foamed article, wherein the foamed article is substantially the same shape as the precursor.
Abstract:
Methods provide a polymer foam having high bonding strength and improved compressive hardness characteristics wherein the polymer foam comprising cavities formed by microballoons, and also 2 to 20 vol. %, based on the total volume of the polymer foam, of cavities surrounded by the polymer foam matrix.
Abstract:
Methods for reducing the density of thermoplastic materials and the articles made therefrom having similar or improved mechanical properties to the solid or noncellular material. Also disclosed are improvements to foaming methods and the cellular structures of the foams made therefrom, and methods for altering the impact strength of solid or noncellular thermoplastic materials and the shaping of the materials into useful articles.