A New Liquid Diol (2,4-Diethyl-1,5-Pentanediol) for Improved Hydrolytic Stability

Kyowa Hakko USA is introducing a new liquid diol, 2,4-diethyl-1,5-pentanediol (PD-9), Figure 1 . Our poster illustrates the use of PD-9 to make adipate polyester polyols for urethane resins. We compare the performance of urethane resins based on PD-9 to resins based on other diols. Urethane resins containing PD-9 have greater hydrolytic stability and can be softer than resins synthesized from other types of diols. Figure 1 Structure of 2,4-diethyl-1,5-pentanediol https://www.w3.org/1999/xlink" xlink:href=" https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003760467/65158eb8-8e4d-450b-86e9-2b264704af35/content/pg521-001.tif "/> In order to compare the properties of PD-9 based urethanes to other diols such as 1,4-butanediol, adipate polyols were made from a number of different glycols. The polyols are then used to synthesize a standard urethane resin. The physical properties and hydrolytic stability of the urethane resins were compared to determine the influence of diol type on urethane performance. The PD-9 based resins are softer than resins based on 1,4-butanediol, neopentyl glycol, or 3-methyl-1,5-pentanediol. However, the PD-9 based resins have better hydrolytic stability. The resin formulation can be adjusted to provide equivalent hardness and still maintain the excellent water resistance of PD-9. Kyowa Hakko’s new diol, 2,4-diethyl-1,5-pentanediol, provides chemists with a new option to control the properties of polyester poloyls for urethane resins.