Cloth.bendingStiffness

Description

Bending stiffness of the cloth.

Must be between zero and one. Setting the value to zero disables bending stiffness simulation.
In many cases, when you want a cloth to be more stiff, actually reducing the number of vertices will get you better results - and performance.

transform.GetComponent.<Cloth>().bendingStiffness = 1;

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void Example() {
        transform.GetComponent<Cloth>().bendingStiffness = 1;
    }
}