Monodisperse Polymer Polyol

Patent Title: PROCESS MAKING POLYMER POLYOL HAVING MONODISPERSE DISPERSED POLYMER PARTICLES

 Number/Link: WO2017/172417

Applicant/Assignee:  Dow

Publication date: 5 october 2017

Gist”: Polymer polyol with a “monodisperse” particle size distribution is prepared by using a specific seeding dispersion

Why it is interesting: It is well known that the use of polymer polyols in flexible polyurethane foam formulations can result in improved airflow and load bearing properties. For optimal results the average particle size of the dispersed polymer needs to be similar to the cell wall thickness. According to this invention a SAN polymer polyol with a controlled and narrow particle size distribution can be prepared by using a seed dispersion which consists of an unsaturated macromer which, together with SAN particles of a particle size between 50 and 500 nm, is dispersed in a base polyol. The macromer is a PO/EO polyether with a (pref.) mole weight of 11000 to 14000 Da and having 4-5 OH groups and 1-2 reactive double bonds. The polymer polyol is prepared by dispersing the seed dispersion in the base polyol together with styrene, acrylonitrile and a solvent (e.g. isopropanol). After polymerization of the monomers the solvent is removed, resulting in a polymer polyol with at least 30% solids, average particle size of 1-3 μm and a size span of 1.25. In the examples the macromer is prepared by capping 1-2 OH groups of a 6-functional 90/10 PO/EO polyol with 3,3-isoprenyl-α,α-dimethylbenzylisocyanate.

3,3-isoprenyl-α,α-dimethylbenzylisocyanate

 

 

Viscoelastic Polyurethane Elastomers

Title:  IMPACT PROTECTION FOAM

Number/Link: US2017/0233519

Applicant/Assignee: Dow

Publication Date: 17 august 2017

“Gist”: Viscoelastic foams are prepared from MDI, castor oil and a hydrophilic polyether polyol.

Why it is interesting: According to this invention energy absorbing foams with relatively low density and a low hardness and resilience in the temperature range from about -10 to +40°C, can be produced by reacting a blend of hydrophilic and hydrophobic polyols containing castor oil, about 0.5 pbw water and some catalyst and chain extender with MDI.  The examples show foams of about 500 kg/m³ with hardness below shore 50A and ball rebound below 15% at both -10 and +23°C. The foams are said to be useful for impact-protective garments.

Castor oil

Castor oil component

Hydrolysis Resistant Polyester Urethane

Patent Title: HIGHLY DURABLE POLYESTER POLYOL

 Number/Link: US2017/0022143

Applicant/Assignee: Kuraray

Publication date: 26-jan-2017

Gist”: PU from polyester polyol with bulky side groups

Why it is interesting: The invention is about polyester polyols prepared from a dibasic acid (e.g adipic acid) and a mixture of two diols: 3-methyl-1,5-pentanediol and cyclohexane-1,1-dimethanol. The diols are used in a molar ratio of about 1:1 (25-75 to 75-25 pref.). Polyurethanes prepared with these polysters are said to be highly hydrolysis resistant in both acidic and basic environments.

Cyclohexane-1,1-dimethanol

Cyclohexane-1,1-dimethanol

Polyether-Polyacetal Polyols

Patent Title: POLYETHER-ACETAL POLYOL COMPOSITIONS

 Number/Link:  WO2016/112274

Applicant/Assignee: Dow

Publication date: 14-07-2016

Gist”: Lewis-acid catalysis for polyactal-modified polyethers

Why it is interesting: According to this application, acetal-modified polyether polyols can be prepared by first reacting a (pref.) di- or trifunctional initiator with PO until about 500 eq. wt. using DMC catalysis. This ‘starter’ polyol is then further reacted (at a lower temperature) with PO using a (pref.) Boron-based lewis acid as catalyst, e.g. tris(pentafluorophenyl)borane. Under these conditions part of the epoxy will isomerize to the corresponding aldehyde.  The aldehyde can then co-polymerize such that part of the polyol will be functionalized with polyacetal. Polyurethanes prepared with these polyols are said to show improved modulus and other mechanical properties.

tris(pentafluorophenyl)borane

tris(pentafluorophenyl)borane

Melt-Dispersed Polymer Polyols

Title: PROCESS FOR MAKING A POLYMER POLYOL

 Number/Link: WO2015/165761  (German)

Applicant/Assignee: BASF

Publication date: 5-11-2015

Gist”: Polymer polyols are prepared by melt-dispersing SAN into a carrier polyol using a specific stabilizer

Why it is interesting: Polymer polyols, or ‘graft polyols’, contain finely dispersed polymeric particles and are especially useful for the production of flexible polyurethane foams.  Usually polymer polyols are produced by in-situ polymerization of styrene-acrylonitrile (SAN)- or polyurea particles in a carrier polyol. In this invention, polymer polyols are prepared by dispersing molten SAN into a carrier polyol using shear mixing and a specific stabilizer.  The stabilizer is a (preferably) comb-shaped polyol-SAN copolymer, and is described in another BASF application: WO2015/165878. The polymer polyols are said to have a fine and uniform particle size distribution, a low viscosity and a high stability against segregation.

SAN

SAN