Adhesive deformulation: how an adhesive or sealant formulation is analyzed
Start with the bond mechanism
An adhesive is not one chemical but a system that must wet a surface, develop cohesion and survive its service environment. A hot-melt adhesive commonly combines a base polymer, tackifying resin and wax; a water-based adhesive places polymer particles or soluble binder in an aqueous phase. A sealant may instead be designed for gap filling, movement and long-term exposure. We therefore ask which behavior matters before interpreting a component list: initial tack, cured flexibility, adhesion to a particular substrate or resistance after aging.
Two materials can share the same broad binder family yet behave differently because resin selection, filler loading or curing package differs. Conversely, a visible performance difference does not prove that the principal polymer changed. A useful comparison names both samples, their condition and the property that prompted the question. For example, a manufacturer comparing two hot melts might ask whether the additive pattern is consistent with a change in tackifier system rather than requesting an exact plant recipe.
The sample changes the question
A supplied hot-melt pellet represents material before application; a cured film represents what remains after application or reaction. During curing, volatile material can leave and reactive groups can become part of a network. The cured article can support questions about the surviving binder and filler, but it cannot be read backwards as the original liquid mixing sheet. If the concern is a failed joint, include the reference and failed materials in comparable states when possible; a difference caused solely by curing history can otherwise be mistaken for a formulation change.
For overseas receipt, we review water-based adhesives, hot-melt adhesives and cured adhesive films; two-component adhesives containing isocyanates and reactive polyurethane hot melts need case-by-case review. We do not receive liquid solvent-based adhesives from overseas, although a cured film or solids fraction may be proposed. Other adhesives and sealants that are neither water-based nor solid, such as cyanoacrylates or uncured silicone sealants, are not received as supplied; a cured bead or film can be proposed. A film cannot preserve the evaporated solvent fraction. We can describe the material actually submitted, not an absent component of the original liquid.
What a useful conclusion looks like
For an adhesive comparison, the strongest conclusion separates an identified compound from a chemical family and an unresolved fraction. An estimated proportion is semi-quantitative, so it is better used to frame a development hypothesis than to copy a mixing instruction. Analysis cannot reveal a raw material supplier or trade name from chemistry alone. We may combine LC-MS/MS, GC-MS and ICP-MS on the same sample as appropriate, with interpretation tied to what the sample supports.
How to start
We accept overseas industrial samples after declaration review. Use the sample declaration form and read the related guide. Our reports are research-grade analytical reports from a laboratory that is not accredited. They cannot be used for product registration or legal proceedings.
Related guides
FAQ
Why can two adhesives with similar main polymers behave differently?
Similar binder families can still differ in tackifier, filler or curing package, each of which can change the joint behavior.
Is a cured sealant bead equivalent to uncured material?
No. A cured bead represents the post-reaction material; volatile ingredients and original mixing ratios may no longer be recoverable.
Can a hot-melt pellet be considered for overseas shipment?
Yes, a hot-melt adhesive is on our reviewable solid and semi-solid sample list. Reactive polyurethane hot melts contain isocyanate and are reviewed case by case, and acceptance always depends on declaration review.
What should I compare when investigating a failed bond?
Compare the failed and reference materials in similar states, and state the substrate, curing history and failure question.
Send a sample declaration for this product and state the question you want answered.