Propolis while also collecting water and tree resin necessary for the production of propolis. The chemical composition and nature of propolis depend on environmental conditions and harvested resources. For centuries, beekeepers assumed that bees sealed the beehive with propolis to protect the colony from the elements, such as rain and cold winter drafts. However, 20th century research revealed that bees not only survive, but also thrive, with increased ventilation during the winter months throughout most temperate regions of the world. Propolis properties may include: The composition of propolis varies from hive to hive, from district to district, and from season to
Wood glue do not adhere well to hardened PVA glue. PVAs will creep under constant load. "Elmer's Glue-All" is an example of PVA adhesive. Aliphatic resin emulsion, commonly referred to as "yellow glue" or "carpenter's glue", has a similar use profile and relative ultimate strength as PVA. The two glues differ in grip characteristics before initial set, with PVAs exhibiting more slip during assembly and yellow glue having more initial grip. Brands include "Titebond" and "Lepage". Contact cement for wood veneers. Hot glue for temporary uses. Homemade glue for paper, wood, and internal uses. Several wood glues have poor "gap-filling" ability, meaning