Investigation of the Effect of Electron Radiation on the Structure of Polypropylene Using Optical and Atomic Force Spectroscopy Methods

Rakhmatullina

et al. 2019

KEM

While producing polymers as well as during their processing, a certain amount of stabilizers is introduced into the product, which should ensure polymer properties saving during processing and those of polymer products during storage and operation. However, in cases where medical products based on polypropylene are subjected to radiation sterilization, there are not enough stabilizers in it to save their characteristics during operation. In this regard, we made an assessment of the influence of processing conditions on the properties of polypropylene with a different set of stabilizers in the manufacture of products based on it, in order to assess the degree of influence of each technological operation, including the effects of ionizing radiation during sterilization. Processing and radiation exposure are shown to affect the properties of polypropylene. Nevertheless, the effect of ionizing radiation with an absorbed dose of 40-60 kGy exceeds the negative effect of thermo-oxidative breakdown greatly during the extrusion of PP. Polypropylene containing organophosphorus stabilizers (brand PP 1562R) is more susceptible to breakdown. This is indicated by low values of oxidation induction time, breakdown initial temperature, as well as high values of MFI after exposure to electron radiation. PP brand PP H350FF/1 whose stabilizing complex contains phenol-phosphite antioxidants is more resistant to breakdown during processing and sterilization. For both brands under study, it is apparently necessary to increase the content of stabilizing additives in order to save the properties at the level of the original unexposed material.

Section: Discussionmentioning

confidence: 99%

Effect of Processing and Radiation Exposure on the Structure and Properties of Polypropylene

Rakhmatullina

et al. 2019

KEM

“…The growth in the volume of consumption of absorbent medical products makes it necessary to expand their range and reduce the cost of materials. One of the most affordable materials is nonwovens made from polypropylene by the spunblown technology [15][16][17][18][19][20][21]. Such materials are hydrophobic in nature.…”

Section: Introductionmentioning

confidence: 99%

Influence of Nonequilibrium Low-Temperature Plasma on the Properties of Nonwoven Fabric Based on Polypropylene

Khakimullin

2021

KEM

Self Cite

Investigation of the effect of low-pressure NLTP in nitrogen, argon, propane-butane and air on the properties of a multilayer medical-purpose material based on polypropylene used for the manufacture of sanitary-hygienic and medical products. It is shown that after plasma treatment of argon, nitrogen, propane-butane, the surface polarity of the CMC material changes significantly, as evidenced by a decrease in the wettability angle and an increase in capillarity. The most significant changes in indicators are observed in the case of plasma treatment in argon and nitrogen. However, in the case of argon, less processing time is required to achieve the effect. Plasma treatment leads to a slight decrease in tensile strength, no more than 10-15%. It is also shown that when plasma is treated in an argon atmosphere, such characteristics of a nonwoven material as air permeability, hygroscopicity increase, and a decrease in rigidity is observed. The study of the structure of the material (pore size) showed that the treatment with NLTP leads to a significant decrease in the size of large pores and an increase in the size of medium and small pores

“…Such materials are made from the most affordable polymer -polypropylene. Despite all the advantages (high strength characteristics, lintfree structure, non-toxicity, anti-static) non-woven spanmelt materials based on polypropylene, have low resistance to radiation sterilization [11][12][13][14][15][16], which is one of the main industrial methods of sterilization of medical devices. Ionizing radiation leads to a decrease in the strength characteristics of non-woven materials based on polypropylene and then products from such materials cease to meet the requirements that apply to them.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Radiation Sterilization on the Stress-Strain Properties of Non-Woven Materials -Based on Polypropylene

Rakhmatullina

et al. 2020

MSF

Self Cite

Non-woven materials are widely used for the manufacture of disposable medical clothing and underwear. Radiation is widely used to sterilize single-use medical devices. The paper analyzes the effect of ionizing radiation at absorbed doses of 0-60 kGy on the stress-strain properties of medical non-woven spanmelt material based on polypropylene obtained by blow-molding technology. It has been established that ionizing radiation significantly reduces the breaking load and elongation in the machine and cross directions of the web. For this type of material, the most critical is the decrease in strength in the cross direction of the web, primarily because the level of strength in the cross direction of spanmelt materials is generally low. Sterilization by ionizing radiation further reduces strength and leads to the fact that non-woven materials irradiated with an absorbed dose of 50-60 kGy are close to unacceptable values in accordance with the requirements of EN 13975-2011.