According to the method of polyethylene glycol 400, starting from "pyridine solution added with phthalic anhydride precisely," the average molecular weight should be 5400-7800.
ອີງຕາມວິທີການຂອງໂພລີເອທິລີນ glycol 400, ເລີ່ມຕົ້ນຈາກ "ການແກ້ໄຂ pyridine ເພີ່ມດ້ວຍ phthalic anhydride ຢ່າງແນ່ນອນ," ນ້ ໍາ ຫນັກ ໂມເລກຸນໂດຍສະເລ່ຍຄວນຈະເປັນ 5400-7800.