** Shares of U.S. Chemical companies are set to end 2025 on a negative note as the sector continues to struggle with weak demand, higher input costs and tightening European regulations

** Chemicals firms serve an array of end markets such as automobiles, building and construction, medical, and electronics

** As of last close, LyondellBasell LYB.N has fallen 41.2%, Eastman Chemical EMN.N has lost ~30%, Dow DOW.N has declined 41.4% and Chemours Co CC.N has lost 30%

** DOW and LYB are among the worst performers on the S&P 500 Materials index .SPLRCM

** "We see risk of degradation in integrated polyethylene margins with more risk of oil-to-gas spread compression and pressure on export markets," Citi analyst Patrick Cunningham said in a note

** Compressed margins and higher ethane costs could weigh on free cash flow and dividend sustainability for DOW and LYB - Cunningham

** Agri-chemical companies: FMC Corp FMC.N and Mosaic MOS.N have fallen 71.4% and 1.8% respectively in 2025

(Reporting by Sumit Saha in Bengaluru)

((Sumit.Saha@thomsonreuters.com;))