I tried this code but :-
$product = $this->_objectManager->create('Magento\Catalog\Model\ResourceModel\Product\Collection')
->addAttributeToSelect('*')
->addAttributeToFilter('entity_id', array('in' => $productIds));
echo '<pre>'; print_r($product->getData()); echo '<pre/>'; die();
Array
(
[0] => Array
(
[entity_id] => 36
[attribute_set_id] => 11
[type_id] => simple
[sku] => 24-MG04
[has_options] => 0
[required_options] => 0
[created_at] => 2016-08-21 07:56:06
[updated_at] => 2016-08-21 07:56:06
)
)
And I am getting this result except of all the attributes.