A neutrons main function is to attract each other and keep the nucleus of an atom intact. They attract each other by the strong nuclear force. However, protons repel each other with the electromagnetic force since they have a charge. Because neutrons have no charge, they are not affected by this force so they can hold the nucleus together better. In summary, neutrons are needed so the nucleus can have more than one proton.

The neutrons are there to hold the protons together via what is known as the strong force, because particles of like charge, such as positively charged protons, naturally repel each other due to the way the electromagnetic force works. The strong force is much, much stronger than the electromagnetic force, and via neutrons hold the protons in the nucleus together. Without it the protons in the atom’s nucleus would fly apart. And it’s the protons which keep the like number of negative electrons in orbit around the atom’s nucleus, via the electromagnetic force.

Hope so it may help you.