JQuery 버튼 수행시간동안 disabled

<style>
button {width:200px; height:100px; }
button:disabled { background: #fee; border:0 }
</style>

<button id='my-btn'>수행</button>

<script src="//code.jquery.com/jquery.min.js"></script>
<script>
  function process(num){
  	$('#my-progress').attr('max', num);
    for(var i=1; i<=num; i++) {
    	console.log('processing '+i);
    	// sleep 1 sec
      ts1 = new Date().getTime()+100;
      do ts2 = new Date().getTime(); while (ts2<ts1);
    }
  }
  
  function async_job() {
  	process(30);
    $('#my-btn').prop('disabled', false);
  }

  $(function() {
    $('#my-btn').click(function() {
      $('#my-btn').prop('disabled', true);
      setTimeout(async_job, 0);
    });
  });
</script>