<?php
$string = "Hello my Name is Paloppa. I'm 20 And? Hello! Words' Man";
// Word boundary before the first uppercase letter, followed by any alphanumeric character
preg_match_all( '/(?<!^)(?<!\. )\b[A-Z][a-zA-Z]*\b(?!["!?\\\'])/', $string, $matches);
print_r( $matches[0] );