Natural glues

These adhesives are soluble or dispersible in water and are produced or extracted from natural sources. Other adhesives, such as rubber cements, nitrocellulose, and ethyl eellulose laequer eements, are also produced from plant sources but are not water soluble or water dispersible and are therefore not classified as vegetable glues.  

These materials will biodeteriorate under humid conditions unless inhibitors are used. Their resistance to heat and weathering is poor therefore, they are restricted to indoor applications. Soybean glues are filled for paper and paperboard lamination, cardboard and box fabrication, and particle binders.  

Rosin family s most common form of adhesive is colophony, a hard amorphous substance derived from 

---

Other natural glues common at the time, such as plant starch and fish glues, were not used for aircraft structure because they are even more sensitive to moisture. 

As polymer chemistry advanced in the 1930s and 1940s, stronger and more durable synthetic adhesives such as early phenol, resorcinol and urea formaldehydes began to supplant natural glues in wood aircraft manufacture. Around this time however, metal began to replace wood as the dominant material for aircraft manufacture. Aerospace adhesives research and development moved on to focus on metals, primarily aluminum, as the substrates of interest. 

An example of 100 percent natural glue is Auro Contact Glue. See www. metaefficient.com/adhesives-caulks-and-sealants/auro-contact-glue-100-natural.html. 

Attempts to combine the natural glues with diisocyanates have led to success. Several tannin adhesive formulations fortified with diisocyanates for particleboards and beechwood have been described in the literature 1-4) ... 

Craft glue or homemade Natural Glue, p. xiv Heavy book, such as a telephone book or dictionary 20 or more large leaves 1 sheet construction paper, 8V2 x 11 inches, different color from the larger one Black marker Scissors... 

Colorful stickers, crayons, or colored markers Craft glue or homemade Natural Glue, p. xiv... 

Craft glue or homemade Natural Glue, p. xiv 8 pieces twine, each 8 inches long 30 or more small pinecones, about 5 inches in length in the shape of a carrot Scissors Rubber cement... 

Craft glue or homemade Natural Glue, p. xiv 2 Styrofoam eggs or two sheets old newspaper crumpled into 2 balls 30 or more yellow dandelion heads 4 wiggle eyes or small black buttons 1 small basket or bowl Bunch of green or dried grasses... 

Think of what happens when you spill a sugary liquid, like a soft drink, on your hands. Real stickiness only develops once the water evaporates. Sugar is a natural glue, but its molecules have to get very close to a surface before they can bond to it. When dissolved in water, sugar flows easily over a surface then, when the water evaporates, a sticky sugar layer remains. 

The following grouping has been found by the author to be convenient. Some of the adhesive types have already been listed. A list of natural glues is presented in Table 4.19. 

---