TentaGel® resins are grafted copolymers consisting of a low crosslinked polystyrene matrix on which polyethylene glycol (PEG or POE) is grafted via an ethyl ether group which increases stability towards acid treatment and minimizes PEG-leaching. The graft copolymer shows modified physicochemical properties which are highly dominated by the PEG moiety (and no longer by the polystyrene matrix) and has hydrophobic and hydrophilic properties. These copolymers are pressure stable and can be used in batch processes as well as under continuous flow conditions. The PEG spacer is in the range of MW 3000 Da. TentaGel® resins have high diffusion rates and excellent swelling in a wide range of solvents from e.g. toluene to water. In this resin Ramage's dibenzocycloheptadiene linker is attached to amino TentaGel®. After Fmoc removal the resin can be acylated and used in Fmoc SPPS. The linker is essentially more acid sensitive than the Rink amide or PAL linker. Therefore, peptide amides can be cleaved with 3% TFA in DCM and thus it's possible to release acid sensitive peptides or protected peptide fragments.