Chemistry
Articles on adhesive technology, rheology and chemistry.
Press start and watch a virtual rheometer twist a disk of acrylic adhesive back and forth: strain and stress swing out of step, and G′, G″ and tan δ build up point by point into the frequency sweep behind the Chang window.
Read morePress start and watch a virtual rotational rheometer measure water in a bob-and-cup geometry: the bob turns, the torque rises and the flow curve and viscosity curve build up point by point – including the Taylor vortices that fool every beginner.
Read moreCan a few rheological 'lab values' predict how strongly a tape will stick – and how it will fail – before the first peel test? An illustrated introduction to peel tests, rheological features, gradient-boosted trees and honest model validation.
Read moreWhy does a sticky note come off cleanly while packaging tape holds for months – and why does a tape from the freezer not stick at all? An illustrated introduction to the Dahlquist criterion, time–temperature superposition and Chang's viscoelastic window.
Read moreHow can you tell what is inside a wrapped gift without opening it? Shake it gently. An illustrated introduction to oscillation tests: phase angle, G′ and G″, amplitude sweeps and frequency sweeps – the fingerprint of every viscoelastic material.
Read moreWhy does a rubber band around old letters lose its grip while staying just as stretched? An illustrated introduction to the relaxation test, the relaxation modulus, relaxation times and the relaxation spectrum – and what they reveal about adhesive tapes.
Read moreWhy does a taped poster slide down the wall overnight – and what comes back when you take it off? An illustrated introduction to creep tests, creep compliance, the Burgers model and the holding power of adhesive tapes.
Read moreWhy does Silly Putty bounce like rubber but flow like honey – and why does bread dough climb up the kneading hook? An illustrated introduction to the Maxwell and Kelvin–Voigt models, the Deborah number and normal stresses.
Read moreWhy does a rubber band stretch so easily while a steel spring hardly moves – and why do both snap back? An illustrated introduction to Hooke's law, the shear modulus, Poisson's ratio and stored elastic energy.
Read moreWhy does ketchup need a shake, why does oobleck turn hard when you hit it, and why does paint stop dripping? How a rotational rheometer measures flow behavior – and how to read the curves.
Read moreWhy does honey flow so much more slowly than water? A visual introduction to shear stress, shear rate and viscosity, starting from the kitchen and ending at the Two-Plate Model.
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