April 24, 2026
Stick to the drama
Paraloid B-72
Paraloid B-72: The museum glue HN can’t stop arguing about
TLDR: Paraloid B-72 is a clear, non-yellowing museum adhesive that’s strong yet flexible and dissolves with common solvents. The community split between delight at this oddly useful niche tool, jokes about “Polaroid,” and debates over how it compares to industrial glues—proof that even glue can spark big nerd energy
Hacker News stumbled into a love letter to museum glue, and somehow Paraloid B-72 became the star. This clear acrylic resin—used to fix broken ceramics, stabilize fossils, and even harden piano hammers—earned instant translation from one commenter as “a stronger, harder, less-brittle, clear wood glue you can dissolve with acetone.” Others marveled that it doesn’t yellow, can be softened with common solvents, and can even be cast into sheets to fill gaps in glass, a trick credited to conservator Stephen Koob at the Corning Museum of Glass. The catch? It’s famously fiddly to apply, which only made the crowd more curious.
Cue the drama: one user called it “the most esoteric post,” wondering how many museum curators lurk on HN, while another deadpanned that they kept reading it as “Polaroid.” The thread split between practical tinkerers asking how it stacks up to MMA (methyl methacrylate) industrial glues and the vibes-only crowd cheering for obscure Wikipedia rabbit holes. A meta-commenter confessed they’d upvoted it earlier and loved seeing it resurface via the second-chance queue. Verdict from the peanut gallery: niche? Absolutely. But irresistibly sticky content—literally and figuratively
Key Points
- •Paraloid B-72 is an ethyl methacrylate–methyl acrylate copolymer thermoplastic resin developed by Rohm and Haas.
- •It is widely used in conservation for ceramics, glass, fossil preparation, piano hammer hardening, and museum object labeling.
- •B-72 is durable, non-yellowing, stronger and harder than PVA, and more flexible than many adhesives, tolerating more stress at joins.
- •It is soluble in acetone, ethanol, toluene, and xylenes; acetone is often the most suitable solvent, and mixtures adjust working time and properties.
- •Fumed colloidal silica can improve workability and stress distribution; cast B-72 sheets are used as glass fill material by conservators.