Morning Market Brief for the C5 Industry Chain (September 15, 2026)

I. Key Points

1. Saudi crude oil pipeline transportation has been disrupted, with Houthi armed forces continuing to exert pressure and exacerbating supply risks, leading to rising international oil prices. NYMEX WTI crude oil futures for the October contract rose by USD 1.34/bbl to USD 101.39/bbl, a month-on-month increase of +1.34%; ICE Brent crude oil futures for the November contract rose by USD 1.07/bbl to USD 105.68/bbl, a month-on-month increase of +1.02%. China INE crude oil futures for the November 2026 contract rose by CNY 19.8 to CNY 776.5/bbl; in the night session, it rose by CNY 45 to CNY 821.5/bbl.

2. As of the 11th, Japanese naphtha closed at USD 982.39/ton, up USD 13.89/ton from the previous trading day. Singapore naphtha closed at USD 105.48/barrel, up USD 2.27/barrel from the previous trading day.

3. Yesterday, domestic prices for major pyrolysis C5 enterprises remained stable, and Shandong mixed C5 prices held steady temporarily. Rising crude oil prices provided some market support. The fuel sector faces enhanced regulatory standards, impacting residual liquid products in certain regions, resulting in a wait-and-see attitude. Regarding deep processing, piperylene monomer prices remained firm, and resin prices were supported by costs, but end-user purchasing enthusiasm remained weak.

4. Yesterday, the domestic pyrolysis C5 residual liquid market maintained stability while executing contracts. Boosted by crude oil, gasoline market conditions in Shandong improved, warming up downstream receiving sentiment. Favorable supply-demand dynamics for homogeneous product mixed C5 ended, leading to price declines. The pyrolysis C5 residual liquid market remained stable while fulfilling contracts, with a predominantly wait-and-see stance.

5. Yesterday, domestic piperylene prices trended slightly upward. High costs provided support, plant supply was relatively tight, and downstream demand was driven by essential needs, keeping the market firm. Mainstream ex-factory prices ranged from CNY 8,700–9,600/ton.

6. Yesterday, domestic isoprene market trends were primarily upward. On-site supply was relatively tight, downstream SIS prices gradually increased, and combined with firm upstream raw material prices, multiple positive factors supported strong prices. Mainstream bid/ask prices in East China ranged from CNY 13,400–14,100/ton.

7. Yesterday, dicyclopentadiene (DCPD) prices continued to rise, ranging between CNY 8,600–9,200/ton. Low-end prices stabilized for existing customers, while some auction prices were slightly higher. Spot supply remains relatively tight, inventories are generally low, and supported by raw material prices, the high-price trend is expected to continue in the short term.

8. Yesterday, mainstream prices for road marking paint C5 petroleum resin ranged from CNY 9,600–10,600/ton. Continued rises in international oil prices and tight domestic C5 resources drove significant price increases, causing local inversion phenomena in some resins. Overall demand continued to rise slightly, pushing negotiated prices higher.

9. Yesterday, mainstream prices for piperylene adhesive C5 petroleum resin ranged from CNY 11,000–13,000/ton, and for de-cyclized adhesive C5 petroleum resin from CNY 10,600–11,000/ton. Spot availability remained tight, and costs continued to rise. Downstream risk aversion was strong, slightly boosting stockpiling enthusiasm. Short-term shortages dominated, pushing negotiated prices higher.

Core Logic: Pyrolysis C5 consolidation, isoprene increase, piperylene slight increase, DCPD increase, and C5 petroleum resin stable with slight upward push.

II. Price Table

Table 1: Domestic Pyrolysis C5 Industry Chain Summary (Unit: CNY/ton)

III. Market Outlook

Domestic pyrolysis C5 prices are expected to remain firm. Crude oil closed significantly higher, and Shandong mixed C5 prices are at high levels, still maintaining a price gap compared to pyrolysis C5. Private enterprise auction prices remain firm. Regarding pentadiene monomers, low inventory supports continued price increases. Resin sales are average, but cost support is strong, driving resin prices upward due to cost pressures.

Pyrolysis C5 residual liquid market trends are expected to weaken slightly. Gasoline refinery inventories are low, providing some basis for holding prices. Favorable supply-demand dynamics in the mixed C5 market have weakened, leading to slight declines. Considering all factors, Chempricehub Information expects today's pyrolysis C5 residual liquid prices at refineries to decline slightly.

Overnight crude oil prices rose. Refinery shipment sentiment for gasoline was good yesterday, suggesting potential price pushes today. Mixed C5 circulation volume increased yesterday with good shipment sentiment; Chempricehub Information expects the mixed C5 market to remain stable and cautious today.

Isoprene is expected to trade firmly. With crude oil closing higher and tight isoprene supply continuing, plants are motivated to hold prices and restrict sales. Prices are expected to consolidate firmly.

Piperylene is expected to consolidate firmly. Recent strengthening of costs, combined with reduced plant output and increased internal consumption, limits tradable resources in the market. Piperylene is expected to continue its firm trend.

DCPD is expected to remain at high levels. Downstream demand performance is average, but spot tightness is unlikely to ease in the short term. Combined with clear cost support from raw material prices and the pre-holiday stocking decision period for Mid-Autumn and National Day festivals, market supply and cost factors will dominate in the short term, maintaining a firm high-level trend.

For road marking paint C5 petroleum resin, downstream construction activity is concentrated in northern regions. Raw material C5 prices have risen significantly. In the short term, resin costs will remain high, and production willingness may decrease for some, leading to further slight price increases. For adhesive C5 petroleum resin, manufacturers face rising cost pressures, and downstream essential demand is increasing, leading to further slight price increases.

IV. Data Calendar

Table 2: Domestic Pyrolysis C5 Industry Chain Data Overview (Unit: 10,000 tons)