The present invention provides hydrogels and compositions thereof for vocal cord repair or augmentation, as well as other soft tissue repair or augmentation (e.g., bladder neck augmentation, dermal fillers, breast implants, intervertebral disks, muscle-mass). The hydrogels or compositions thereof are injected into the superficial lamina propria or phonatory epithelium to restore the phonatory mucosa of the vocal cords, thereby restoring a patient's voice. In particular, it has been discovered that hydrogels with an elastic shear modulus of approximately 25 Pa are useful in restoring the pliability of the phonatory mucosa. The invention also provides methods of preparing and using the inventive hydrogels.