According to the commodity market analysis system of Business Society, as of January 31, the price of DOP (dioctyl phthalate) was 8,017.50 yuan per ton, a significant increase of 9.44% compared to 7,325.84 yuan per ton on January 1. By February 4, the DOP price had dropped to 7,950.84 yuan per ton, a decrease of 0.83% compared to 8,017.50 yuan per ton on January 31.

In January, the operating load of DOP producers slightly decreased, with an operating rate of approximately 63%, leading to a reduction in DOP output. The prices of raw materials, isooctanol and phthalic anhydride, rose sharply, increasing production costs for DOP. Combined with the reduced supply, these factors drove a significant price increase for DOP in January. In February, DOP producers slightly increased their operating rates, boosting supply. However, as pre-holiday stockpiling neared completion, demand declined, resulting in a price drop for DOP.

Slight Decrease in DOP Producer Operating Rates in January
In January, the operating load of DOP producers slightly decreased, with the operating rate dropping from 68% in December to 63%. This led to a decline in DOP output and supply, maintaining upward pressure on DOP prices. In February, the operating rate of DOP producers is around 64%, increasing output and ensuring ample supply.

Significant Increase in Isooctanol Prices
As of January 31, the quoted price for isooctanol was 7,880 yuan per ton, a substantial increase of 13.93% compared to 6,916.67 yuan per ton on January 1. By February 4, the price had dropped to 7,716.67 yuan per ton, a decrease of 2.07% compared to 7,880 yuan per ton on January 31. Following the completion of equipment maintenance, isooctanol producers increased their operating load to 95%, ensuring sufficient supply. The sharp rise in propylene prices further strengthened cost support for isooctanol. The significant increase in isooctanol prices raised production costs for plasticizers, intensifying upward pressure on DOP prices. In February, isooctanol prices retreated from their highs, reducing plasticizer production costs.

Sharp Rise in Phthalic Anhydride Market in January
As of January 31, the quoted price for ortho-phthalic anhydride was 6,243.33 yuan per ton, a significant increase of 4.64% compared to 5,966.67 yuan per ton on January 1. By February 4, the price had dropped to 6,200 yuan per ton, a decrease of 1.33% compared to 6,283.33 yuan per ton on January 27. The increase in the price of raw material ortho-xylene raised production costs for phthalic anhydride, leading to fluctuating but overall rising prices in January. This increased DOP production costs and strengthened support for plasticizer price increases. In late January, the price of industrial naphthalene fell, and ortho-xylene prices stabilized weakly, reducing phthalic anhydride production costs and leading to fluctuating price declines. Consequently, plasticizer production costs decreased, weakening support for price increases.

Growth in Plasticizer Demand
On January 8, 2026, the Ministry of Finance and the State Taxation Administration issued an announcement clarifying that the 13% VAT export rebate for plasticized PVC will be canceled from April 1, 2026, aligning with the policy for unplasticized PVC and PVC resin. Plasticized PVC, also known as flexible PVC, relies heavily on plasticizers (such as DOTP, DOP, etc.) to adjust flexibility and is widely used in wires and cables, artificial leather, films, hoses, and other fields. To benefit from the final rebate incentive before April 1, companies in this sector accelerated order scheduling, and overseas clients concentrated their purchases, temporarily boosting export volumes and driving phased growth in plasticizer demand. Pre-holiday stockpiling also provided some support for downstream orders, increasing plasticizer demand.

Future Outlook
Business Society's plasticizer product data analyst believes that, in terms of costs, the sharp rise in isooctanol and phthalic anhydride prices in January significantly increased cost support for DOP, driving a substantial price increase. In February, the decline in isooctanol and phthalic anhydride prices reduced DOP production costs. In terms of supply, plasticizer producers maintained a weakly stable operating rate in January, with output slightly decreasing. In February, operating rates increased, boosting output and ensuring ample supply. Regarding demand, the export rebate incentive drove downstream demand growth, leading to phased increases in plasticizer demand in February and March. However, as pre-holiday stockpiling neared completion, demand began to decline. Looking ahead, with decreasing costs, ample supply, and slowing demand growth, DOP prices are expected to experience weak consolidation.