The most well-liked epoxy resins are possibly diglycidyl ethers of bisphenol A, and that is created by reacting bisphenol A (BPA) with epichlorohydrin (ECH). the molecular body weight is managed by modifying the ratio of ECH to BPA; superior ratios deliver lessen molecular weights. Waterproofing adalah teknik membuat atap / https://www.propanraya.com/kategori/cat-lantai