“…Flexoelectric effects have been observed and widely studied in hard materials (Tolpygo, 1963, Kogan, 1964, Hong and Vanderbilt, 2011, Resta, 2010, Maranganti et al, 2006, mainly crystalline ceramics such as ferroelectric perovskites (Zubko et al, 2007, Ma and Cross, 2001a, Fu et al, 2006, Ma and Cross, 2001b, 2003. However, they are also present in soft materials, such as liquid crystals (Meyer, 1969, Petrov, 1975, Prost and Marcerou, 1977, Harden et al, 2006, Trabi et al, 2008, cellular membranes (Petrov et al, 1989, Todorov et al, 1991, 1994, Sun, 1997, Petrov, 2002 and polymers (Breger et al, 1976, Marvan and Havránek, 1998, Baskaran et al, 2011, Deng et al, 2014c, Zhang et al, 2016b, Zhou et al, 2017.…”