UV-crosslinkable acrylic hotmelt pressure sensitive adhesives comprising acrylic and vinyl monomers, and a polymerizable UV photoinitiator. The photoinitiator comprises a spacer comprising both ethylene oxide and urethane, or urea, carbonate, or siloxane functional groups. The ethylene oxide is directly bonded to the chromophore (e.g., benzophenone) moiety, while the urethane (or urea, carbonate,siloxane) is closely linked to the polymerizable moiety (e.g., styrenic C=C double bond).