Concept:Natural adhesives are bio-based polymeric substances derived directly from animal, plant, or dairy proteins and carbohydrates without synthetic polymerization.
Formula / Reaction:Qualitative concept / No formula required.Solution:- Casein glue is a natural adhesive manufactured by precipitating casein phosphoproteins from skimmed milk using dilute acid or rennet, followed by alkaline dissolution.
- It has been used historically in woodworking, bookbinding, and label bonding.
Why other options are incorrect:- Silicones: Synthetic inorganic-organic polymers with a repeating \(-\text{Si}-\text{O}-\) backbone.
- Polyvinylacetate: A synthetic thermoplastic resin prepared by the addition polymerization of vinyl acetate.
- Polyamide: Synthetic condensation polymers containing repeating amide linkages.
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