Why is DCP (di-sec-octyl phthalate) still relevant when DOTP is overtaking DOP in China's plasticizer market?

Why is DCP (di-sec-octyl phthalate) still relevant when DOTP is overtaking DOP in China's plasticizer market?
DCP sits in an unusual niche within China's phthalate plasticizer complex. Unlike DOP, which is made from 2-ethylhexanol, DCP is esterified from secondary octanol, giving it a different volatility and solvency profile that some PVC formulators still prefer for specific flexible applications. One domestic producer already holds leading DCP capacity alongside its mixed dibasic acid dimethyl esters and diol series, and is adding 60,000 t/y of multifunctional environmentally friendly plasticizer capacity. The broader market backdrop matters: phthalates still account for roughly 80% of total plasticizer output, and about 80% of that volume goes into PVC and vinyl copolymers. Soft PVC typically carries 45-50% plasticizer by weight, so even a shrinking DCP share represents meaningful tonnage. The real pressure comes from the regulatory side, where non-phthalate DOTP is displacing ortho-phthalates in cables, films and consumer goods.