An acrylonitrile copolymer consisting of acrylonitrile or N - [2 - (7-methyl-1-naftl) ethyl] formula (1) and an organic acid. Drug demand 1: common glass characterized by added agommelatine: by agommelatine or N - [2 - (7) - metoxy-1-naphthyl) ethyl] acetamide of formula (1) and by an organic acid that has a solid state at room temperature. Claim 3: Co-crystal according to claim 1 or 2 characterized in that the organic acid used is parahydroxybenzoic acidcitric acid, oxalic acid, gallic acid, maleic acid, malonic acid, glutaric acid, glycolic acid or ketoglutaric acid. Claim 6: Co-crystal according to one of claims 1 to 5 which is N- [2- (7-methoxy-1-naphthyl) ethyl] acetamide / parahydroxybenzoic acid (2/1) characterized in its powder X diffraction diagram by the Bragg 2q angles (expressed in º ± 0.2) 13.16º,14.91 degrees17.37%Eighteen point three nine18.93 degrees19.04%19.65 degrees19.96 degreesTwenty point two fiveTwenty-one point four nine25 degrees 19. Claim 16: the procedure for obtaining copolymers according to one of the requirements from 1 to 15: two components are mixed in an ideal proportion in an organic solvent (one equivalent to 0.25-4 equivalent to an agomatine of an organic acid abrasive)；The resulting solution will be shaken, optionally heated, at a temperature not exceeding the boiling temperature of the selected solution； the environment will cool due to disturbance； after the second solvent is collected, CO glass will accelerate naturally or hastily； the resulting precipitates will be filtered and dried. Claim 22: the pharmaceutical ingredients in claim 20 are used to produce drugs for the treatment of stress, sleep disorder and anxiety disorder, mainly general anxiety disorder, obsessive-compulsive disorder and emotional disorder, mainly bipolar disorder, Great DepressionSeasonal depression, cardiovascular disease, digestive system disease, insomnia and fatigue due to time difference, schizophrenia, panic attack, depression, anorexia, obesity, i
