Artificial　synaptic　transistors　have　shown　great　potential　in　artificial　intelligence　due　to　their　low　energy　consumption,　high　scalability,　similarity　to　biological　neurons　and　precise　regulation　of　channel　conductance.　A　key　step　to　achieving　multifunctional　synaptic　transistors　is　to　regulate　synaptic　weight　in　a　fixed　synaptic　device　using　the　same　materials.　However,　the　intrinsic　properties　of　the　films　used　for　this　purpose　are　affected　by　some　uncertain　factors,　such　as　complicated　processing　and　poor　accuracy.　Herein,　a　multifunctional　synaptic　transistor　based　on　a　thermo-denatured　polar　polymer　material　poly(2-acrylamido-2-methyl-1-propanesulfonic　acid)　(PAMPSA)　is　reported.　Typical　synaptic　characteristics　such　as　excitatory　post　synaptic　current　(EPSC),　paired　pulse　facilitation　(PPF)　and　long　term　potentiation　(LTP)　were　successfully　simulated　under　different　annealing　temperatures.　More　importantly,　we　have　demonstrated　that　the　polarization　degree　of　PAMPSA　was　directly　influenced　by　the　annealing　temperatures,　and　that　even　small　temperature　changes　(＜20　degrees　C)　would　allow　a　wide　regulation　range　of　synaptic　weight,　indicating　that　the　synaptic　weight　can　be　modulated　purposefully　and　precisely.　Hence,　this　work　provides　a　simple,　convenient　and　accurate　approach　to　regulate　synaptic　weight　and　the　memory　retention　of　an　artificial　synapse　via　modulation　of　the　annealing　temperature,　which　facilitates　a　wide　simulation　range　of　artificial　synapses　and　the　development　of　artificial　neuromorphic　devices.