1. Explain the following observations: (i) Kevlar has an extremely high tensile strength and melting temperature. (ii) At room temperature, poly(methylmethacrylate) is transparent, while polyethylene is translucent. At temperatures above 135°C, both polymers are transparent. (iii) Polyoxymethylene and polyethylene exhibit similar mechanical behaviour. However, the glass transition temperature of polyoxymethylene is about 50°C higher than that of polyethylene.

1. Explain the following observations: (i) Kevlar has an extremely high tensile strength and melting temperature. (ii) At room temperature, poly(methylmethacrylate) is transparent, while polyethylene is translucent. At temperatures above 135°C, both polymers are transparent. (iii) Polyoxymethylene and polyethylene exhibit similar mechanical behaviour. However, the glass transition temperature of polyoxymethylene is about 50°C higher than that of polyethylene.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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