The most early produce HPEG is from May 2010 in China,however,many foreigners don't know it,everything need to say from TPEG.
Use raw material TPEG synthetic Polycarboxylate Superplasticizer, not only have high water reduction,but also have high slump retention ,good adaptability to cement ,simple production process and equipment,so many factory have good graces in it.
But it has the disadvantage of insufficient supply of raw materials.Then put into production HPEG have good resolved the short of TPEG,and many factory start to produce it.The water reduction rate is not different from that of the water reducing agent produce from TPEG,but in summer the slump retention is not better than TPEG,although,HPEG have charming price in market.
General HPEG will be go bad under temperature 35~40,expiration date only have a week or several month,in winter have low temperature will lasting date of store.
If you find that HPEG has begun to degenerate,please use it as soon as possible.