The curing of unsaturated polyester resins (UPR) is accompanied by a high degree of polymerization shrinkage of about 7-10%, resulting in poor dimensional stability, surface quality and mechanical properties. Low profile additives (LPA) are thermoplastic materials that are highly effective in eliminating polymerization shrinkage in high temperature molding processes, such as compression molding of sheet molding compounds (SMCs) and injection molding of bulk molding compounds (BMCs). Polymethylmethacrylate (PMMA) copolymers are among the most important LPAs. Besides the excellent low-shrinkage properties, the application of PMMA copolymers results in high thermostability of the end product (≥ 200°C) combined with good mechanical performance. All these properties make our DEGALAN® LP 53/13C and DEGALAN® 6639 products the materials of choice for applications in the automotive and electrical sector. The sold in solid form are applied in the SMC/BMC mixture as a styrenic solution.