We shared some common problems and solutions in the production process of polyureyhane elastomers last time; Below we will comtinue to share more problems and solutions that attract the attention of producers.

 6. How to dry the main raw materials

(1) The polyol is dried in a high-temperature, vacuum, stirred, and vibrating device

(2) Drum drying, nitrogen drying

7. The reaction speed is too fast

(1) The alkalinity is too high

(2) The amount of catalyst is too much

(3) Increasing the temperature too quickly (every 10 degrees Celsius increase, the life in the kettle is shortened by 2 times)

8. The reaction speed is too slow

(1) The amount of catalyst is insufficient

(2) The reaction temperature is too low

9. Improve wear resistance

(1) Use appropriate main raw materials, especially hard section materials

(2) Use Teflon additives

10. Improve the gentleness of gentleness

(1) Use higher molecular weight polyether polyols instead of polyester polyols

(2) Use PTMEG instead of PPG

11. Improve high temperature resistance

(1) Use high-performance raw materials, especially chain extenders and isocyanates (such as HQEE, PPDI)

(2) Use more stable antioxidants

12. How to improve the compression perpetual change

(1) Use appropriate primary raw materials

(2) Use a trifunctional chain extender

(3) A higher NCO index is used

(4) Optimize the mixing temperature

(5) Use trifunctional isocyanates

13. How to reduce energy absorption

(1) Use raw materials with linear polymerization, do not form branched chains, and form good hard segment properties

14. How to make transparent PU

(1) Reduction of crystallinity of hard sections (suitable processing conditions and/or with special chain extenders)

(2) Change NCO%  

Qichen can provide elastomer prepolymers of TDI, MDI, polyether, polyester and PTMEG types,etc. And committed to providing customers with customized raw materials and solving a series of technical problems at the same time.