Chapter 5Adhesives and coatings
Chapter 5 Adhesives and coatings
ContentsIntroductionFHistory General terms Basic properties Basic chemistryTheories of adhesion Type of adhesivesAdhesive resinsApplication
Contents ◼ Introduction ◼ History ◼ General terms ◼ Basic properties ◼ Basic chemistry ◼ Theories of adhesion ◼ Type of adhesives ◼ Adhesive resins ◼ Application
5.lAdhesives5iIntroductiontoadhesion&adhesivesNatural gluesfrom plants &animals (a) Animal glues were mostly based onmammalian collagen, which is the mainprotein of skin, bone and sinew. (b) The plant kingdom provided starchesand dextrins from corn, wheat, potatoesand rice
5.1 Adhesives 5.1.1 Introduction to adhesion & adhesives ◼ Natural glues —— from plants & animals ◼ (a) Animal glues were mostly based on mammalian collagen, which is the main protein of skin, bone and sinew. ◼ (b) The plant kingdom provided starches and dextrins from corn, wheat, potatoes and rice
Synthetic adhesivesused in all types ofmanufacture- (a) Shoes(b) Aircraft(c) Automobile & railway- (d) Human beings
◼ Synthetic adhesives —— used in all types of manufacture ◼ (a) Shoes ◼ (b) Aircraft ◼ (c) Automobile & railway ◼ (d) Human beings
Disadvantages & advantages of adhesivesDisadvantages:They are generally weakened by water and itsavapor.Their service temperature ranges are less than(b)for metal fastenersAdvantages:
◼ Disadvantages & advantages of adhesives ◼ Disadvantages: (a) They are generally weakened by water and its vapor. (b) Their service temperature ranges are less than for metal fasteners ◼ Advantages: