There are no surface build finishes that will stand up to extended exposure to ultra violet & suns rays. Given that you are talking about your boats interior and it is not excessively exposed to sun, a non porous surface finish that you can apply would be some sort of polyurethane. Since teak is an open pored wood, you will need to apply 3-4 thin coats sanding between each coat to get the finish you are looking for, a lot of work. If you are using semi gloss you must be careful to suspend the goo in the bottom of the can in the finish with extended stirring just prior to application. You also should not have applied any oil type finishes recently on the teak prior to applying poly to the teak. This could cause a problem in the curing of the poly. There are other finishes that are superior to ploy but nothing that you can apply relatively trouble free- toxic fumes, difficulty of application etc. If you were to apply multiple coats of the oil type finish, over a long period of time you would build up a surface finish, much like the Scandinavian wipe finished furniture. An alternate formula for this type of finish is 10% polyurethane, 30% tung oil, 60% linseed oil. This will produce this type of finish with many coats, again a lot of work of wipe on, let set, wipe off. You must burn or get rid of the wiping rags as they are prone to spontaneous burning. Given all of the above is why people use the pledge oil.
Good luck