Process for preparing coated shaped bodies and their use
A process for coating particles of an expanded thermoplastic elastomer involves a1) bringing the particles into contact with a water-based binder, resulting in at least partly coated particles, and a2) drying the coated particles. A process for the preparation of a shaped body involves b) coating the particles of the expanded thermoplastic elastomer, wherein before a2) the particles are brought into the shape of the shaped body, or wherein after a2) the particles are brought into the shape of the shaped body and contacted with a solvent, preferably a water-based solvent, or by subjecting the particles to heat. A shaped body is obtainable by such processes. A water-based binder is useful for the preparation of a shaped body, wherein the shaped body is formed by particles of an expanded thermoplastic elastomer and wherein the particles are at least partly coated with the water-based binder.
1 . A process for preparing a shaped body, the process comprising:
a1) bringing particles of an expanded thermoplastic elastomer into contact with a water-based binder, resulting in at least partly coated particles;
a2) drying the at least partly coated particles; and
b2 1 ) after the particles are dried in a2), the particles are brought into the shape of the shaped body and thereafter the particles are contacted with a solvent, or are subjected to heat, or both wherein the particles are contacted with a solvent and are subjected to heat; or
b2 2 ) after the particles are dried in a2), the particles are contacted with a solvent, or are subjected to heat, or both wherein the particles are contacted with a solvent and are subjected to heat, and thereafter are brought into the shape of the shaped body.
2 . The process of claim 1 , wherein the particles are brought into the shape of the shaped body and contacted with a solvent.
3 . The process of claim 2 , wherein the solvent is a water-based solvent.
4 . The process of claim 1 , wherein the particles are brought into the shape of the shaped body by subjecting the particles to heat.
5 . The process of claim 1 , wherein the contacting with a solvent or the subjecting the particles to heat is carried out before the shaping.
6 . The process of claim 1 , wherein the contacting with a solvent or the subjecting the particles to heat is carried out after the shaping.
7 . The process of claim 1 , wherein the expanded thermoplastic elastomer is expanded thermoplastic polyurethane.
8 . The process of claim 1 , wherein the water-based binder is an aqueous polymeric dispersion.
9 . The process of claim 8 , wherein the particles in the aqueous polymer dispersion have a minimum film formation temperature (according to DIN ISO 2115:2001-04) below 70° C.
10 . The process of claim 9 , wherein the aqueous polymer dispersion is an aqueous polystyrene acrylic dispersion, an aqueous acrylic dispersion, an aqueous butadiene/styrene dispersion, or an aqueous polyurethane dispersion.
11 . The process of claim 1 , wherein the water-based binder is an aqueous polymeric solution.
12 . The process of claim 11 , wherein the aqueous polymeric solution is an aqueous polyvinylpyrrolidone solution.
13 . The process of claim 1 , wherein the particles of the expanded thermoplastic elastomer are brought into the shape of the shaped body by filling a negative form of the shaped body with the particles.
14 . The process of claim 1 , wherein the particles of the expanded thermoplastic elastomer are brought into the shape of the shaped body by hand forming the particles.
15 . The process of claim 1 , wherein at least one of a1), a2), or a1) and a2) are carried out at room temperature.