The sentence is difficult to understand because there is more than one possibility what it might mean. For example, "Each one of quite a few scientists has made several expeditions." "Quite a few scientists have gone together on several expeditions." Why not just say "Many scientists have made expeditions to Antartica" ?

Yes, your sentence sounds natural, but you can make it even smoother by making a slight adjustment: "Many Chinese scientists have participated in several scientific expeditions to Antarctica." This version maintains the same meaning while flowing a bit more smoothly.