---
title: "Epoxy and adhesive"
subject: "Civil Engineering Materials"
chapter: 10
key: "semester_3/civil_engineering_materials:epoxy-and-adhesive"
source: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/epoxy-and-adhesive
site: BCT Engineering
---

# Epoxy and adhesive

Civil Engineering Materials · Chapter 10: Asphalt, Bitumen, Tar and Miscellaneous Materials

- Asked in: 2078 Bhadra, 2 marks
- Video: [Epoxy Basics from Old Mission Boat Company](https://www.youtube.com/watch?v=EAa6gLYvgqE) — Old Mission Boat Company
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/epoxy-and-adhesive
- Whole chapter: https://www.bctengineer.com/md/semester_3/civil_engineering_materials/chapter-10

## Question

What is epoxy and adhesive?

## Short answer

An adhesive is a substance that bonds surfaces by adhesion and cohesion, used for tiles, laminates, and repairs. Epoxy is a two-part thermosetting resin that cures to form a strong, hard, cross-linked solid with excellent adhesion to concrete, metal, and glass, high strength, low shrinkage, and chemical resistance; used for structural bonding, crack injection, grouting, and coatings.

## Answer

#### Adhesive

An **adhesive** is a substance that joins two surfaces and holds them together by sticking to them (adhesion) and by its own internal strength (cohesion). Examples: animal glue, starch paste, gum, synthetic resin glues, cement-based adhesive and epoxy. Adhesives are used for fixing tiles, laminates, wood joints and flooring, and for repair work.

#### Epoxy

**Epoxy** is a thermosetting synthetic resin supplied in two parts, **resin** and **hardener**. When they are mixed, a chemical reaction forms a very strong, hard, cross-linked solid.

- Excellent adhesion to concrete, metal, glass, wood and stone.
- High strength, small shrinkage, and resistance to water, chemicals and abrasion.
- Used for bonding old and new concrete, crack injection, grouting of anchors, floor coatings, tile adhesives and fibre-reinforced polymers.

Epoxy is therefore a special, high-performance structural adhesive.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. An adhesive does what?
   A. Joins two surfaces by sticking and internal strength
   B. Dissolves surfaces
   C. Insulates sound
   D. Colours surfaces
   Answer: A. It holds surfaces by surface attachment and internal strength. (Key point: Adhesive)

2. Epoxy is supplied as what?
   A. One part powder
   B. Two parts: resin and hardener
   C. Sheets
   D. Gas
   Answer: B. Mixing resin and hardener gives a cross-linked solid. (Key point: Epoxy parts)

3. Epoxy is what kind of resin?
   A. Thermoplastic
   B. Thermosetting
   C. Natural
   D. Cement
   Answer: B. A thermosetting resin. (Key point: Epoxy class)

4. Epoxy is used for what?
   A. Bonding old and new concrete and crack injection
   B. Wire sheath
   C. Bricks
   D. Roof tiles only
   Answer: A. Also anchor grouting, floor coatings and FRP. (Key point: Uses)