Science Buddies: "Ask an Expert"

Hello Experts!

I am helping my 7th grade son with a project. He wants to test the strength of various brands and types of PVA glue to find out which is the strongest. Knowing the ingredients of the various types does not help him with the actual experiment, but it would perhaps influence his hypothesis as well as help him understand why they performed differently in his experiments. I have done a lot of searching on brand websites and MSDS sheets but no one details the ingredients (or percentages of ingredients). Is it possible to find the answer? The glues he is testing are: Elmer's Xtreme, Elmer's Glue-All, Elmer's School Glue, pen GEAR School glue (Walmart brand), Gorilla Wood Glue, Aleen's Original Tacky Glue, and Aleene's Clear Gel Tacky Glue (which I am not sure is actually a PVA glue, since it's clear).

Thanks!
Sarah Mollenkopf

Hello!

Most of the glues you are testing are based on PVA, but they may include other ingredients that affect strength. For example, Elmer's Xtreme and Gorilla Wood Glue probably have stronger formulas of PVA or added polymers for better bonding, especially on wood. Aleene's Original Tacky Glue is thicker and stickier to help in crafting projects, while Aleene's Clear Gel Tacky Glue may not be pure PVA and may include other resins to keep it clear. Elmer's School Glue and pen GEAR School Glue are basic PVA glues, so they may be less strong but fine for general use. Moreover, the strength is determined by the amount of PVA, chemicals added to give it flexibility or make it quick-drying, and surface being bonded. Try out your luck!