Hello Freiberg,
There's optional "frame" argument in the .exportModel() method, so you need to loop through all frames and export them individually:
for frame in range(chunk.frame_count):
export_path = export_folder + "\\model_" + str(frame) + ".obj"
chunk.exportModel(path = export_path, texture_format = "jpg", texture = True, format = "obj", frame = frame)