Special technology has been developed for the production of polypropylene surgical monofilaments to meet medical needs for a suture material meeting tight specifications for physical and mechanical properties. To produce polypropylene monofilaments having improved elastic properties and strength, studies have been made on the effects of technological parameters (temperatures of liquid and of cooling bath, molding rate, thermal drawing ratios and temperatures, the thermal stabilization temperature, and temperature of additional thermal treatment of existing monofilaments with or without shrinkage) as regards the strength, elongation, the strength and elongation in knots, and bending rigidity. Conditions are given for making surgical monofilaments of various diameters with improved manipulation and strength.Polypropylene (PP) monofilaments are amongst the best nonresorbed suture materials, as they have high biocompatibility, good strength, resistance to biodegradation, lack of capillary performance, and reliable fixation of surgical knots. They have smooth surfaces and are monolithic, so they produce minimal damage on passing through tissues while providing a good cosmetic effect and reducing the painful sensations on removing the sutures. However, the characteristic rigidity means the risk of shearing of the tissues in the formation of wound swelling and difficulty in manipulation during operative intervention.The technical PP monofilaments produced by Russian industry cannot be used as surgical materials because of their low elasticity and consequently their low strength in knots, which usually does not exceed 50% of the strength of the monofilament. The strength in knots is a basic characteristic of a suture material, and it determines the reliability of the surgical procedure, so that parameter is to be found in the standardization documentation of EP and USP [1, 2].Medicine requires a material subject to tight specifications for the physicomechanical properties, so a special production technology is needed. The monofilament properties can be improved by physical modification, which is best combined with the making of the monofilaments.Monofilaments were made from isotactic polypropylene grade 21030; stabilization recipe 16 was used, which is permissible for medicine. The fluidity parameter for the liquid polymer was 2.5-4.0. The melt method was used to make the PP monofilaments, which was implemented with a continuous technological scheme on a plant made by the Italian firm of Covema.There are the following stages in making PP monofilaments: transporting and loading the polymer, melting the polymer, shaping (casting in a tank and preliminary drawing), thermal drawing, thermal stabilization, winding on a coil, and monitoring the physicomechanical properties, sorting, and packing. To improve the visualization of the filaments in a wound background, we added 0.2-0.3% of pigments permitted in medicine: phthalocyanin blue or green. In that case, the granulate before loading into the extruder bunker was treated with...