The present invention relates to expanded thermoplastic polyurethane beads, a preparation method for same, and an application thereof. The expanded thermoplastic polyurethane beads consists of components of the following parts by weight: 100 parts of a thermoplastic polyurethane, 1-10 parts of a cell size stabilizer, and 1-35 parts of a melt viscosity modifier. The preparation method for the expanded thermoplastic polyurethane beads is also disclosed. The bead is produced by employing a volatile blowing agent to immerse the thermoplastic polyurethane, comprising the pore size stabilizer and the melt viscosity modifier, in an aqueous suspension, and is then followed by the foaming process. Utilization of the expanded thermoplastic polyurethane beads of the present invention allows for preparation of a foam product. The expanded thermoplastic polyurethane beads prepared per the present invention has uniform cell sizes and a high product yield. At the same time, the expanded thermoplastic polyurethane bead provides a great sintering performance even at a relatively low vapor pressure, a molded foam product has a small deformation, a low dimensional shrinkage ratio relative to a mold, great dimensional stability, and an aesthetically appealing appearance.

Curable compositions are provided which comprise: a) 30-80 wt % of a room temperature liquid epoxy resin; b) 0.5-10 wt % of an epoxy curative; c) 5-40 wt % of a thermoplastic resin; and d) 0.5-10 wt % of a physical blowing agent. In some embodiments, the curable compositions may be fire retardant. In some embodiments, the curable compositions may be used in the form of films, and more particularly as core splice film adhesives.

PLA polymers that can be expanded into microporous articles having a node and fibril microstructure are provided. The fibrils contain PLA polymer chains oriented with the fibril axis. Additionally, the PLA polymers have an inherent viscosity greater than about 3.8 dL/g and a calculated molecular weight greater than about 150,000 g/mol. The PLA polymer article may be formed by bulk polymerization where the PLA bulk polymer is made into a preform that is subsequently expanded at temperatures above the glass transition temperature and below the melting point of the PLA polymer. In an alternate embodiment, a PLA polymer powder is lubricated, the lubricated polymer is subjected to pressure and compression to form a preform, and the preform is expanded to form a microporous article. Both the preform and the microporous article are formed at temperatures above the glass transition temperature and below the melting point of the PLA polymer.

To obtain a modified polypropylene-based resin which shows specific viscoelasticity and from which an expanded sheet having a low open cell ratio can be obtained.

An expanded bead having a tubular shape with a through hole and a method for producing the same are provided. The expanded bead includes a foamed core layer and a covering layer. A polyolefin-based resin included in the covering layer has a melting point lower than a melting point of a polypropylene-based resin included in the foamed core layer. An average hole diameter d of the through hole of the expanded bead is less than 1 mm, and a ratio d/D of the average hole diameter d to an average outer diameter D of the expanded bead is 0.4 or less. The polypropylene-based resin for the foamed core layer has a flexural modulus of 1,200 MPa or more and a melting point of 158° C. or lower.

A spray foam formulation used to form a spray foam insulation layer in a wall structure is described. The formulation may include the reaction product of a polyisocyanate compound and a polyol compound; a fire retardant chosen from at least one of a non-halogenated fire retardant; and a reactive halogen-containing fire retardant, and a carbohydrate. The spray foam insulation layer has an insulative R value of 3.0 to 7.2 per inch, and a density of between about 0.3 to about 4.5 pcf. Further, spray foam insulation made from the spray foam formulation may have fire retardant characteristics that are equivalent to or better than a similar spray insulation foam insulation using non-reactive halogenated fire retardants such as tris(1-chloro-2-propyl)phosphate (TCPP).

This disclosure describes micro-, sub-micron, and nano-cellular polymer foams formed from siloxane containing (co)polymers and blends, and systems and methods of formation thereof. The micro, sub-micron, and nano-cellular polymer foam has a density of less than or equal to 300 kg/m.sup.3.

This invention relates to the use blends comprising HFO-1336mzz-Z, methyl formate, and optionally, HFC-152a as blowing agents for thermoplastic polymers (e.g., polystyrene).

This invention relates to the use of HFO-1336mzz-Z/cyclopentane blends as blowing agents for thermoplastic polymers (e.g., polystyrene).

4-methyl-1-pentene based resin foam containing a 4-methyl-1-pentene based resin, and having an expansion ratio of 3 times or more is prepared. When measured in a decalin solvent at 135° C., an intrinsic viscosity [η] of the 4-methyl-1-pentene based resin may be 0.5 to 5 dl/g. The 4-methyl-1-pentene based resin may have a glass transition temperature of 0° C. to 80° C. The 4-methyl-1-pentene based resin may have a melting point. The 4-methyl-1-pentene based resin may be a 4-methyl-1-pentene/C.sub.2-20α-olefin copolymer (in particular, 4-methyl-1-pentene/C.sub.2-4α-olefin copolymer). The expansion ratio of the 4-methyl-1-pentene based resin foam may be 10 times or greater.