Developed by: Marjan Polymer Industries. Pakistan

Project In-charge: Dr. Muhammad Abid

Collaborators: Prof. Dr. Tahir Jamil (late), Prof Dr. Khan, Dr. Nafisa

Year: 2014 

Polyurethanes belongs to class of alternating segmented polymers which comprises mainly two alternative segments such as soft and hard segments. The Polyurethane dispersions were made by dispersing amphiphilic pre-polymers using soft segment (polyol), hard segment (diisocyanates), and internal emulsifier followed by chain extension steps.

Adopted Synthesis Process

The pre-polymer process. This technique is used to produce polyurethane coatings, elastomers and sealants.

 

2 OCN–R–NCO + HO ~~~~~~~~~ OH

(Oligo-diol)

OCN–R–NHCOO ~~~~~~~~~~ OCONH–R–NCO

(Pre-polymer)

This pre-polymer having free NCO terminals which further reacts with chain extenders and the resulting polymer (polyurethane) formed is a high molecular weight polyurethane.

OCONHRNHCOO ~~~~~~~~~~~~OCONHRNCO + HO–R1–OH

(Pre-polymer) (Diol)

O–R1–O [CONHRNHCOO ~~~~~~~~~~~ OCONHRNHCOO–R1–O]n

(Polyurethane)

Results:

  • Transparent Coating
  • High Hardness
  • Excellent UV Protection
  • Excellent Impact Resistance
  • Excellent Chemical Resistance
  • High Gloss
  • Good Scratch Resistance
  • Good Rheological Flow
  • Excellent Colloidal Stability