On the Pummel Test and Pummel-Value Evaluation of Polyvinyl Butyral Laminated Safety Glass

2021 ◽

Author(s):

Rike Brendgen ◽

Carsten Graßmann ◽

Thomas Grethe ◽

Boris Mahltig ◽

Anne Schwarz-Pfeiffer

Keyword(s):

Mechanical Properties ◽

Chemical Resistance ◽

Crosslinking Agent ◽

Polyvinyl Butyral ◽

Polymer Dispersion ◽

Safety Glass ◽

Enhanced Properties ◽

Multifilament Yarns ◽

Textile Coating ◽

Recycled Material

AbstractPolyvinyl butyral is used in safety glass interlayers, mainly in car windshields. Legislative regulations require a recycling of cars after their lifetime and therefore also their safety glass. This causes the availability of recycled polyvinyl butyrate (r-PVB) originated from safety glass interlayers. Due to deteriorated optical properties, such as the transparency, and unknown amounts of plasticizers, it is challenging to reuse the recycled material in new windshields. Therefore, it is of particular interest to find new fields of application for r-PVB, such as the usage as a textile coating. In this research, r-PVB was investigated as a material for yarn coating. Polyester and polyamide mono- and multifilament yarns were coated continuously with solely a polymer dispersion and with mixtures of crosslinking agent and polymer dispersion. Crosslinked r-PVB coatings showed enhanced properties toward abrasion and chemical resistance. Coatings without the crosslinking agent showed a diminished abrasion resistance and could be washed off with ethanol. Mechanical properties of the monofilaments were influenced by the r-PVB coating in general. However, varying concentrations of the crosslinking agent did not affect the mechanical properties.

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Investigations on the execution and evaluation of the Pummel test for polyvinyl butyral based interlayers

Glass Structures & Engineering ◽

10.1007/s40940-020-00120-y ◽

2020 ◽

Vol 5 (3) ◽

pp. 371-396

Author(s):

Miriam Schuster ◽

Jens Schneider ◽

Tuong An Nguyen

Keyword(s):

Film Surface ◽

Polyvinyl Butyral ◽

Test Method ◽

Structural Element ◽

Binary Images ◽

Free Film ◽

Safety Glass ◽

High Adhesion ◽

Adhesion Level ◽

Pull Tests

Abstract Laminated safety glass (LSG) is increasingly used as structural element in buildings. Of central importance for safety are the adhesion and the residual load-bearing capacity in the post fractured state. In literature a large number of tests to assess adhesion is mentioned. These include, e.g. peel tests, through-cracked-tensile/-bending tests, VW-pull tests and compressive shear tests. However, especially in industry, the Pummel test is widespread for determining the quality of adhesion in LSG with polyvinyl butyral based interlayers. This test method proves to be simple and quick to carry out: The laminate is stored at − 18 °C and then completely destroyed at room temperature with hammer blows. The adhesion level (0–10) is determined by visually comparing the adhering glass fragments with reference pictures or with the help of diagrams and tables which indicate the Pummel value as a function of the free film surface. Pummel value 0 is to be interpreted as no adhesion and Pummel value 10 as very high adhesion. Due to the lack of standardization, the execution and evaluation is very much dependent on the test institution and executive person. This paper shows different Pummel classifications that can currently be found on the market. Subsequently, approaches to the automatization and standardization of the execution and especially the evaluation of the Pummel test are shown. Three image evaluation methods in Matlab are presented, discussed and compared: (1) analysis of binary images, (2) statistical evaluation of the greyscale images and (3) texture analysis using co-occurrence matrices.

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Synthesis, properties and application in polyvinyl butyral of spirooxazine photochromic compounds

Pigment & Resin Technology ◽

10.1108/prt-12-2018-0125 ◽

2019 ◽

Vol 48 (5) ◽

pp. 421-430 ◽

Cited By ~ 1

Author(s):

Liemei Yuan ◽

Gang Cai ◽

Jun Gao

Keyword(s):

Thermal Stability ◽

Fatigue Resistance ◽

Polyvinyl Butyral ◽

Ring Closure ◽

Content Type ◽

Safety Glass ◽

Synthesis Properties ◽

Covalently Linked ◽

Fading Rate ◽

Photochromic Materials

Purpose The purpose of this paper is to evaluate the effect of antioxidant 2,6-di-tert-butyl-p-methylphenol (BHT) on the thermal stability and fatigue resistance of spirooxazine and then study the properties of photochromic polyvinyl butyral resin (PVB) films. Design/methodology/approach BHT was introduced into the spirooxazine system by blending and covalent bonding. The properties of spirooxazine solutions and photochromic PVB films were studied. Findings The thermal stability and fatigue resistance of spirooxazine covalently linked (BHT-SO) or mixed (BHT/SO) with BHT were higher than the system without BHT, and BHT-SO was the better one. But acidic substance would greatly impair the fatigue resistance of spirooxazine. The optimum addition amount of BHT-SO2 to PVB was 2.5 per cent, and the minimum limit was 0.01 per cent. The fading kinetic and fatigue resistance of film were similar to the solution and better. Plasticizer could accelerate the fading rate and strengthen the mechanical properties of photochromic film but had no effect on the fatigue resistance. Research limitations/implications Spirooxazine could be grafted onto the PVB chain to make the ring closure fading reaction slower. Practical implications In addition to the wide application prospects of photochromic materials in decoration, optical storage, etc., the photochromic PVB film in the car safety glass can absorb sunlight and turn blue, then fade to colorless when the sunlight disappears, making the interior environment more comfortable. Originality/value The introduction of BHT into the spirooxazine system not only exerts its ability to capture free radicals, but its bulky volume also increases the resistance of the ring closure, making the fading process slower.

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The Recycling of Waste Laminated Glass through Decomposition Technologies

Recycling ◽

10.3390/recycling6020026 ◽

2021 ◽

Vol 6 (2) ◽

pp. 26

Author(s):

Ľubomír Šooš ◽

Miloš Matúš ◽

Marcela Pokusová ◽

Viliam Čačko ◽

Jozef Bábics

Keyword(s):

Automobile Industry ◽

Window Glass ◽

Weather Conditions ◽

Polyvinyl Butyral ◽

Laminated Glass ◽

Chemical Cleaning ◽

Safety Glass ◽

Mechanical Separation ◽

Glass Recycling ◽

Technical Safety

Laminated glass is ever more frequently used nowadays. This applies to the automobile industry and the construction industry. In cars, this refers mostly to the front and rear windows, whereas in construction, technical safety glass is used for railings and window glass. The task of this type of glass is to provide sufficient resistance against mechanical impact and unpleasant weather conditions. At the same time, if it is damaged, it has to break into the smallest possible pieces, or, wherever possible, the glass should remain intact on the interlayer film to prevent shards from injuring people and animals in the immediate vicinity. The paper deals with the recycling of laminated glass, especially with the effective separation of glass (in the form of cullet) from the polyvinyl butyral (PVB) interlayer film. The experimental research is focused on the mechanical separation of glass from the interlayer film by vibration, and also on the chemical cleaning of PVB film in order to allow subsequent recycling of both materials. The results quantify the efficiency of mechanical separation in the form of weight loss of the sample of laminated glass and define the particle size distribution of glass cullet, which is an important parameter in the possibility of glass recycling. The research leads to a methodology proposal for the separation of glass and PVB film and the design of equipment for this method.

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