שאלה | A number of extreme changes occur upon covalent chemical crosslinking of polymers. Which one of the statements is true? (Choose from the following four possibilities)

A number of extreme changes occur upon covalent chemical crosslinking of polymers. Which one of the statements is true? (Choose from the following four possibilities)

		Decreasing crosslink density: Increases rigidity which can give brittle polymers
		Crosslinking is frequently used to decrease the crystalline transition temperature Tm.
		In elastomers (rubbers) the crosslink density is low to allow large reverible deformations
		One major effect is that linear polymers no longer have a glass transition temperature.