Chemicals had a broad up week while the wider market sold off: all nine names rose over seven days (from DuPont's +0.35% to LyondellBasell's +6.63%), six of nine now sit above their 200-day averages against one a week ago, and nothing is left in the RSI 25–40 band. Air Products ($APD, +18.33% over one year, 4.1% over its line) has the cleanest long trend; Dow ($DOW) and DuPont ($DD) have strong one-year records but remain under their 200-days, and Sherwin-Williams ($SHW) is back over its line with the group's weakest alpha.

Data as of the 2026-10-16 close for all nine tickers, including the materials fund ($XLB), from the desk's chemicals summary (Polygon bars). Comparison: the October 9, 2026 scan.

The tape change is a full-breadth rally in a week the S&P 500 had its worst since June (Bloomberg, October 16). Seven-day changes as of the October 16 close: LyondellBasell +6.63%, Air Products +6.52%, Dow +5.31%, Sherwin-Williams +4.96%, PPG +3.3%, $XLB +3.01%, Linde +3.04%, Ecolab +2.51% and DuPont +0.35%. Friday was mixed: LyondellBasell +2.14%, Linde +1.06%, Air Products +1.01% and Dow +0.91% rose, while DuPont (-0.87%), Ecolab (-0.66%), Sherwin-Williams (-0.51%) and PPG (-0.39%) slipped. Volume was ordinary or light for most, but Ecolab traded at 2.79 times its average and PPG at 2.18 times, the two heaviest, on small down moves. Over thirty days seven names are positive (Linde +7.86% best) and only Dow (-0.5%) and LyondellBasell (-1.37%) are negative.

Long-horizon structure improved at the 200-day line but not in the multi-year records. Air Products is closest to an intact trend: +18.33% over one year, alpha +2.8, golden cross, 4.1% above its 200-day, 4.85% off its 52-week high. Linde (+12.2%, alpha -3.33, 1.8% above), $XLB (+15.65%, alpha +0.12, only 0.1% above its line) and Ecolab (+6.75%, alpha -8.78, 5.1% above) are over the line with returns that match or trail the market. LyondellBasell (+39.58% over one year, alpha +24.05) is 1.8% above its 200-day but -30.36% over two years with its 50-day still under the 200-day, so this is a rebound inside a long loss. Sherwin-Williams is 0.6% above its line with +1.13% over one year, -13.92% over two and alpha -14.4. Under test: DuPont (+33.02% over one year, +21.85% over two, alpha +17.49) is 5.5% under its 200-day with a strong-down tag, and Dow (+36.67% over one year, alpha +21.13, but -43.46% over two) is 7.3% under; PPG is 4.2% under with a strong-down tag, -17.62% over two years and alpha -9.22.

No cause is on file for the week's rise or for Friday's volume. The news pulls for Dow, Air Products, Ecolab and LyondellBasell were taken October 13–15, before Friday's session, and hold quote pages and earnings-call material from earlier quarters; the DuPont (September 11), Linde (July 31) and Sherwin-Williams (July 25) pulls are older, and the PPG pull failed and is stale from June (a rate-limit error), so news was not pulled for these moves. Six Form 4 filings from PPG insiders were filed October 16; the capture does not parse their codes or values, so nothing can be said about them. A LyondellBasell Form 4 the same day is a share withholding of 152 shares ($9,525.84). Crude rose sharply Friday on Iran's escalation in the Strait of Hormuz (CNBC, October 16) and Bloomberg ties Friday's equity drop to that and to AI worries; neither item names a chemical company, so any link to these moves is cause not checked in this scan.

• Seven-day breadth: nine of nine positive, from seven of nine; the smallest gain is now +0.35% and the largest +6.63%, against +2.97% at the top a week ago.
• Thirty-day breadth: seven of nine positive, from three; only Dow and LyondellBasell are negative.
• Names above the 200-day: six of nine (Ecolab, Air Products, Linde, LyondellBasell, Sherwin-Williams, $XLB), from one (Ecolab). Still under: Dow, DuPont, PPG.
• RSI 25–40 band: empty, from one (PPG 38.9 to 52.9). The lowest reading is DuPont at 48.4; the highest are Linde (67.8) and Air Products (65.3), against 56.8 for the leaders on October 9.
• Dow's strong-down tag turned weak-up; its 200-day gap narrowed from -11.6% to -7.3% but is still the deepest.
• Sherwin-Williams' one-year return turned from -4.16% to +1.13%; its alpha is still the worst.
• DuPont and PPG are the two names still on a strong-down short tag.

RSI measures recent buying versus selling pressure on a 0–100 scale; under 30 is oversold and 25–40 is the watch band used below. The short trend tag reads only the last few weeks. The longer-horizon checks are the gap to the 200-day average, the one- and two-year changes, and one-year alpha (return versus the market); for Dow and LyondellBasell the two-year change matters because strong years sit inside deep two-year losses. None of these names carries a desk thesis rating, so everything here is raw price evidence, not a setup. A week of rising RSIs on a broad bounce is not by itself a trend change. Table values show each row's data date; prose figures are as of the October 16 close.

Capitulation, RSI under 25: None.

Oversold, RSI 25–40: None. The band held PPG (38.9) on October 9; every name is now 48 or higher.

Neutral to strong, RSI 40+: DuPont (48.4), PPG (52.9), $XLB (58.3), Sherwin-Williams (58.6), Dow (60), LyondellBasell (62.9), Ecolab (63.4), Air Products (65.3) and Linde (67.8) as of October 16. Nothing is above 70; Linde and Air Products are the most extended.

• Whether the six names over their 200-days hold them on the first pullback, starting with the thinnest cushions: $XLB (0.1%), Sherwin-Williams (0.6%), Linde and LyondellBasell (1.8% each).
• Reports (provider estimates): Dow October 22 before the open; Sherwin-Williams and Ecolab October 27 before the open, PPG October 27 after the close; Linde October 29, LyondellBasell October 30, DuPont November 3, Air Products November 5.
• Dow's 200-day at $32.28, with a base pivot near $32.05 (October 16 summary): a close through both would turn the rebound into a structural repair.
• DuPont's 200-day at $138.04 and PPG's at $112.08, the lines that would end their strong-down tags.
• Fresh news for PPG, whose last pull failed, and for the names whose receipts predate Friday; any chemical company statement tying costs or demand to crude.

• Tape: the desk's chemicals summary as of the 2026-10-16 close (chemicals).
• Comparison: the October 9, 2026 chemicals scan (2026-10-09-chemicals).
• Market context: Bloomberg, October 16, 2026, S&P 500 suffers worst week since June as AI fears hit chipmakers and CNBC, October 16, 2026, Brent oil touches $110 as Iran escalates Hormuz attacks (2026-10-16-*).
• News receipts: stocks{DOW,LYB,SHW,APD,LIN,ECL,PPG,DD,XLB}/news/latest.json` (DOW, APD fetched 2026-10-15 evening PT; ECL 2026-10-13; LYB 2026-10-12; XLB 2026-10-14; DD 2026-09-11; LIN 2026-07-31; SHW 2026-07-25; PPG failed and stale since 2026-06-21).
• Filings: PPG Form 4s 2026-10-16-ppg-4-0000079879-26-000306 through -000312.md (codes not parsed); LyondellBasell Form 4 2026-10-16-lyb-4-0002062500-26-000010.
• Report schedule: stock-events rows in research/stock-events/ for DOW (2026-10-22), SHW, ECL, PPG (2026-10-27), LIN (2026-10-29), LYB (2026-10-30), DD (2026-11-03), APD (2026-11-05); all provider estimates.
• Captures for October 10–16 searched for all nine company names; no article or social item names them.