DOCSLIB.ORG

Polyurethane Thin-Film Welding for Medical Device Applications Manufacturers Seeking to Replace PVC Or Latex Must Understand How Bonding Processes Affect Materials

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Polyurethane Thin-Film Welding for Medical Device Applications Manufacturers Seeking to Replace PVC Or Latex Must Understand How Bonding Processes Affect Materials September 2002 http://www.devicelink.com/mddi DesignDesign andand DevelopmentDevelopment Learning from Failure: How to Profit from Prototyping Setbacks Improve Product Development with Innovation Mapping Understanding Sterilization Options, p. 52 The Ins and Outs of Welding Polyurethane, p. 62 A Canon Communications LLC Publication THERMOPLASTICS Polyurethane Thin-Film Welding for Medical Device Applications Manufacturers seeking to replace PVC or latex must understand how bonding processes affect materials. Tilak Shah HERMOPLASTIC FILMS properties; and reductions in have been used in flexible the thickness of a film can medical product applica- lower costs and increase the tions since the 1960s, when area obtained from a given plasticized polyvinyl weight of polymer yield per chloride (PVC) blood square meter.2 Tstorage bags replaced glass bottles.1 In Amorphous polymers re- the 1970s, PVC became the material of spond better to welding than choice for Band-Aids, and a decade later crystalline polymers do be- the use of polymeric film patches in sur- cause they soften, melt, and gical draping became popular, replacing resolidify gradually. Howev- latex films. In the 1990s, the use of organ er, some amorphous resins bags, drug-delivery patches, and breath- with high melting points, able films for wound care increased dra- such as polycarbonate and matically, making films much in demand polysulfones, are difficult to in the medical industry. However, health weld.3 Crystalline polymers, and environmental concerns about PVC In selecting films for medical devices, designers which have high, more de- and latex films have driven the develop- must consider several factors. fined melting points, tend to ment of alternative materials for these ap- melt and resolidify quickly, plications (see sidebar on p. 65). WELDABILITY OF THERMOPLASTICS making them challenging to weld. Among Nearly all thermoplastics can be used in the crystalline polymers are polyethylene, film form as thin, soft, flexible, elas- Films most commonly used in the polypropylene, nylon, thermoplastic tomeric materials that can be folded or medical industry include high- and low- polyesters, acetal, and polyphenylene creased without damage. In selecting density polyethylene and polypropylenes sulfide. films for medical devices, designers must from the polyolefin family, plasticized Thermoplastic polyurethane, an aro- consider a variety of factors, including PVC, polyurethane elastomers, and matic or aliphatic polymer, is well suited cost, biocompatibility, sterilizability, me- breathable specialty films such as for use in flexible medical products such chanical toughness, elasticity, optical clar- polyester. Designers need a clear under- as storage and collection bags and many ity, leachability, barrier properties, drug standing not only of a material’s proper- other types of flexible containers and sim- interaction, and sealing and assembly ties, but also of how a particular welding ilar articles. characteristics. process will affect it. Polyurethane films offer some impor- The weldability of plastics is affected tant advantages over other films, includ- by various factors, including type of poly- ing PVC. They have similar welding char- Health and environmental concerns are mer; resin grade; presence of plasticizers, acteristics to PVC, provide strength equal prompting manufacturers to seek out lubricants, and other additives; and mois- to PVC in a thinner film, contain no plas- new applications for materials such as ture content. Thermal properties, molec- ticizers, are sterilizable by either EtO or polyurethane. To make effective use ular characteristics, and crystallinity of a gamma radiation, and have good alcohol of this material, however, designers polymer affect processing and film prop- resistance. Polyurethane films also can be must understand how it responds to erties; additives influence extrusion and readily sealed using radio frequency (RF) various bonding processes. orientation processes and improve film welding techniques. Photo courtesy of POLYZEN INC. THERMOPLASTICS Process Mechanism Special Features Suitable Materials Flame bonding Natural gas flame Continuous web application PVC to foam lamination Hot air gun Hot air or nitrogen Plastic welding rods Low melting plastic, PE Hot knife welding Heat from metal surface Bond in one plane Thermoplastic rubbers Hot plate welding Hot tool/die Draft angle of bar High temperature plastics Induction/impulse Resistance wire Straight line seal Olefins, low temperature films Dielectric – RF Loss in alternative electrostatic field Quick bonding Polar or amorphous elastomer Ultrasonic welding High-frequency compressive loading Sonic conductor Rigid plastics Solvent bonding Material swell/dissolve Chemical fusion Amorphous resin Table I: Fusion welding processes. Adapted from Encyclopedia of Polymer Science and Engineering (New York: Wiley). FILM-JOINING METHODS Response Material Loss Index Welding processes commonly used in (G=good, F=fair, P=poor, N=none) assembling medical devices from ther- ABS polymers 0.025 F–P moplastic films include RF welding, also known as dielectric sealing; ultra- Acetal resin 0.025 F–P sonic welding; direct thermal sealing; Cellulose acetate 0.15 F induction welding or sealing, and sol- DAP 0.04 F vent bonding (see Table I). Selecting the best process for bonding thin-film ma- Epoxy 0.12 F terials in the assembly of medical prod- Melamine 0.2 G ucts involves a number of considera- tions. The material itself is the primary Phenal formaldehyde 0.2 G factor. Size of the product, volume, pro- Polyamide 0.16 F cess capability, cycle time, and cost are Polycarbonate 0.03 F–P other critical variables. In each welding process, controlled PVDF 0.04 F heat is applied to the materials, caus- Polyester 0.05 F ing the plastic to melt in a narrow zone Polyethylene 0.0008 N at the joint interface. Pressure is applied and, once the heat is cut off, the mate- Polyimide 0.013 P rial cools and resolidifies, forming a PMMA 0.09 F weld bond. The amount of compression used is important, since too little or too Polypropylene 0.001 N much can result in a weak seal. A Polystyrene 0.001 N smooth, uniform bead along the weld PTFE 0.0004 N line is ideal. RF Welding. RF welding, a form of di- FEP 0.001 P electric heating, is one of the most wide- PVDF 0.05 F ly used methods for assembling medical devices. The process offers consistent PU film/foam 0.4 G quality; thin, strong weld lines; short seal- PVC film, flexible 0.4 G ing cycles for high output; minimal ther- TPE 0.13 F mal distortion of the film or substrate; and the ability to produce weld-edge tear Silicone 0.009 P–N seals. Of these, the most important ad- Urea formaldehyde 0.2 G vantage is extremely thin weld seams. Im- pulse welding and hot-bar sealing produce Table II. Response of polymers to dielectric heating. Adapted from JD Ferry, Viscoelas- a seal area that is about 1/8 in. wide—too tic Properties of Polymers (New York:Wiley, 1970), and S Saito and T Narajiman Jour- wide for some medical applications. For nal of Applied Polymer Science 2:1959, 93. applications such as containers, the width of the seam is not significant, but for im- ing must be poor conductors of electrici- lene, polystyrene, silicone, and rubber are plantable medical devices, a thinner seam ty, since a good conductor would act as among the materials that are not respon- is preferred. a short circuit, weakening the field near sive to the process. Polymers with strong The materials to be joined by RF weld- the conductor. Polyethylene, polypropy- dipoles respond best to RF welding. The THERMOPLASTICS POLYURETHANE FILM AS AN ALTERNATIVE TO PVC AND LATEX MATERIAL CHOICES nel, such as nurses and lab technicians, are For example, successful RF welding of particularly at risk for latex sensitivity be- polyurethanes requires special die designs, PVC. The most commonly used mate- cause of their high exposure to the material.7 modifications to conventional equipment, rial in the manufacture of flexible medical NRL alternatives include nitrile rubber, syn- and adjustments to the parameters of the devices, PVC has come under fire owing to thetic latex, styrenic elastomers, poly- welding process. The die determines the concerns about the use of phthalates as urethane, and silicone. width of the seam. A typical die design in- plasticizers and environmental problems Thermoplastic Polyurethanes. Ther- corporates an insulated knife that cuts and with disposal. The softness, flexibility, and moplastic polyurethanes contain no plasti- seals the film in one step. Using conven- low-temperature characteristics of PVC cizer and have a lower density than PVC, tional RF welding equipment with thin are determined by the type and amount of producing a higher film yield. The films films produces excessive arcing and weak plasticizer used in the compound. The most offer toughness and strength, and high water- seams. It is a technology that requires high- widely used plasticizer, di-ethylhexyl ph- vapor permeability. They can be sealed using level skills. thalate (DEHP), has been linked to toxic RF welding. Soft formulations can be dip effluents produced during manufacturing molded into gloves, although the process is CONCERNS ABOUT PVC and to the generation of hydrogen chloride more expensive than welding during incineration. Environmentalists Polyurethanes are thermoplastic rubbers Human exposure to DEHP can occur in have raised concerns that the disposal of made from isocyanates and are designated the
Load more

Recommended publications
  • Welding of Plastics: Fundamentals and New Developments
    REVIEW ARTICLE D. Grewell*, A. Benatar Agricultural and Biosystems Eingineering, Iowa State University, Ames, IA, USA Welding of Plastics: Fundamentals and New Developments serves as the material that joins the parts and transmits the load This paper provides a general introduction to welding funda- through the joint. In welding or fusion bonding, heat is used to mentals (section 2) followed by sections on a few selected melt or soften the polymer at the interface to enable polymer welding processes that have had significant developments or intermolecular diffusion across the interface and chain entan- improvements over the last few years. The processes that are glements to give the joint strength. Each of these categories is discussed are friction welding (section 3), hot plate welding comprised of a variety of joining methods that can be used in (section 4), ultrasonic welding (section 5), laser/IR welding a wide range of applications. This paper is devoted to welding (section 6), RF welding (section 7) and hot gas/extrusion weld- processes only. Accordingly, only thermoplastics are consid- ing (section 8). ered, because thermosets cannot be welded without the addi- tion of tie-layers such as thermoplastics layers. Greater details on welding processes can be found in several monographs [1 to 4]. 1 Introduction to Joining Welding processes are often categorized and identified by the heating method that is used. All processes can be divided Despite designers’ goals of molding single component pro- into two general categories: internal heating and external heat- ducts, there are many products too complex to mold as a single ing, see Fig.
    [Show full text]
  • Joining of Fibre-Reinforced Polymer Composites
    JOINING OF FIBRE-REINFORCED POLYMER COMPOSITES A Good Practice Guide ACKNOWLEDGEMENTS The authors and editor would like to thank: Dr Annabel Fitzgerald, National Composites Centre, for reviewing the guide Robin Bilney, Testia Ltd, for reviewing Section 8 Non-destructive testing (NDT) Dr Lawrence Cook, bigHead Bonding Fasteners Ltd, for text and images on bigHeads Chris Minton, Minton, Treharne & Davies, for use of the text and figures on vibrational analysis Prof James Broughton, Oxford Brookes University, for support in adapting Table 8: Comparison and Rating of Disbonding Techniques. Adapted from Lu, Broughton, et al 63 Providers of other images as attributed This guide was funded by the National Composites Centre. Authors Chris Worrall, TWI Ltd Ewen Kellar, TWI Ltd Charlotte Vacogne, TWI Ltd Edited by Stella Job, Grazebrook Innovation © Composites UK Ltd, January 2020 2 CONTENTS 1. Introduction 6 1.1 Scope 6 1.2 Joining in design and specification 7 2. Goals and challenges 8 2.1 Do we need joining at all? 8 2.2 Reasons for joining composites 8 2.2.1 Functionality 9 2.2.2 Manufacturability 9 2.2.3 Cost 9 2.2.4 Aesthetics 9 2.3 Challenges 10 3. Joining possibilities 11 3.1 Types of joints 11 3.2 Joining techniques 11 4. Mechanical fastening 12 4.1 Introduction 12 4.2 Mechanical attachment 13 4.3 Mechanical fasteners 13 4.3.1 Special fasteners for composite structures 14 4.3.2 Types of fastener material 15 4.4 Machining of fastener holes 15 4.4.1 Mechanical machining 15 4.4.2 Non-mechanical machining 17 4.5 Failure modes 18 4.6 Parameters in mechanical fastening 19 4.6.1 Joining method (bolts or rivets) 20 4.6.2 Joint configuration 21 4.6.3 Geometric parameters 21 4.6.4 Lay-up (stacking sequence) 21 4.6.5 Fastener clearance 22 4.6.6 Preload or initial clamping force 23 4.7 Environmental effects on mechanical joints 23 4.8 Advantages and disadvantages of mechanical fastening 23 5.
    [Show full text]
  • STATE-OF-THE-ART in RIGID P.V.C. PLASTIC WELDING by HOT AIR TECHNIQUE Mahmood Alam1, (Dr.) M.I
    International Journal of Technical Research and Applications e-ISSN: 2320-8163, www.ijtra.com Volume 1, Issue 2 (may-june 2013), PP. 20-23 STATE-OF-THE-ART IN RIGID P.V.C. PLASTIC WELDING BY HOT AIR TECHNIQUE Mahmood Alam1, (Dr.) M.I. Khan2 1Asstt. Professor, department of Mechanical Engineering 2 Professor, department of Mechanical Engineering Integral University, Lucknow, India while others are semi-crystalline [6]. When PVC is heated it Abstract: This paper presents the state-of-the-art in the will soften [5, 6], that allow a limited amount of chain field of plastic welding to assist in the future entanglements to assure a strong bond. developments in this field. Various important P.V.C. plastics welding parameters such as welding techniques HOT AIR TECHNIQUE in common use, equipments requirement and the effect of variables on the weld bead shape, have been discussed. Hot air technique is an external heating method. In this Problem associated with plastic welding and applications method, a weld groove and a welding rod are simultaneously have also been outlined. heated with a hot gas stream until they soften sufficiently to fuse together; the welding rod is then pressed into the weld Keywords: Poly vinyl chloride, P.V.C. welding, hot air groove to affect welding. A stream of hot air or gas technique, High-density polyethylene, linear low density (nitrogen, air, carbon dioxide, hydrogen, or oxygen) is polyethylene. directed toward the filler and the joint area using a torch. A INTRODUCTION filler rod or tap (of a similar composition as the polymer being joined) is gently pushed into the gap between the Now a day’s plastics are used in everyday life from substrates (Fig1).
    [Show full text]
  • Products Evolved During Hot Gas Welding of Fluoropolymers
    Health and Safety Executive Products evolved during hot gas welding of fluoropolymers Prepared by the Health and Safety Laboratory for the Health and Safety Executive 2007 RR539 Research Report Health and Safety Executive Products evolved during hot gas welding of fluoropolymers Chris Keen BSc CertOH Mike Troughton BSc PhD CPhys MInstP Derrick Wake BSc, Ian Pengelly BSc, Emma Scobbie BSc Health and Safety Laboratory Broad Lane Sheffield S3 7HQ This report details the findings of a research project which was performed as a collaboration between the Health and Safety Executive (HSE) and The Welding Institute (TWI). The project aim was to identify and measure the amounts of products evolved during the hot gas welding of common fluoropolymers, to attempt to identify the causative agents of polymer fume fever. Carbonyl fluoride and/or hydrogen fluoride were detected from certain fluoropolymers when these materials were heated to their maximum welding temperatures. Significant amounts of ultrafine particles were detected from all of the fluoropolymers investigated when they were hot gas welded. The report concludes that fluoropolymers should be hot gas welded at the lowest possible temperature to reduce the potential for causing polymer fume fever in operators. If temperature control is not sufficient to prevent episodes of polymer fume fever, a good standard of local exhaust ventilation (LEV) should also be employed. This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy. HSE Books © Crown copyright 2007 First published 2007 All rights reserved.
    [Show full text]
  • A Research Paper on the Fundamentals of Plastic Welding
    ISSN (Online) 2394-2320 International Journal of Engineering Research in Computer Science and Engineering (IJERCSE) Vol 4, Issue 8, August 2017 A Research Paper on the Fundamentals of Plastic Welding [1] S Kennedy [1] Department of Mechanical Engineering, Galgotias University, Yamuna Expressway Greater Noida, Uttar Pradesh Email id- [email protected] Abstract: Plastic is a material including a wide scope of semi-engineered or manufactured organics that are malleable and can be formed into strong objects of various shapes. Today, joining of thermoplastic composite structures is getting increasingly huge since thermoplastic composite materials are being utilized to supplant metallic or thermoset composite material to all the more likely withstand different loads in car, aviation, rural apparatuses and marine businesses. Plastic welding is accounted for in ISO 472 as a procedure of joining mollified surfaces of materials, with the assistance of warmth. Welding of thermoplastics is practiced in three progressive stages, as follows surface planning, utilization of warmth or potentially weight, and cooling. Various welding techniques have been developed for the joining of plastic materials. This paper presents advancement one of the tourist plastic welding where the sight- seeing is utilized to circuit or soften a filler thermoplastic pole and at the same time heat the surfaces to be joined. If there should arise an occurrence of hot-gas welding the parameters of welding, for example, welding temperature, stream rate, feed rate, welding power, gas, edge, filler bar, Pressure of tourist/gas, Gap separation and shoe impact the quality of the welded joint. The presentation of the above created machine was completed by getting ready seven examples of fluctuating welding, feed rate keeping different parameters steady all through the analyses.
    [Show full text]
  • Advances in Ultrasonic Welding of Thermoplastic Composites: a Review
    Downloaded from orbit.dtu.dk on: Oct 06, 2021 Advances in Ultrasonic Welding of Thermoplastic Composites: A Review Bhudolia, Somen K.; Gohel, Goram; Leong, Kah Fai; Islam, Aminul Published in: Materials Link to article, DOI: 10.3390/ma13061284 Publication date: 2020 Document Version Publisher's PDF, also known as Version of record Link back to DTU Orbit Citation (APA): Bhudolia, S. K., Gohel, G., Leong, K. F., & Islam, A. (2020). Advances in Ultrasonic Welding of Thermoplastic Composites: A Review. Materials, 13(6), [1284]. https://doi.org/10.3390/ma13061284 General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. materials Review Advances in Ultrasonic Welding of Thermoplastic Composites: A Review Somen K. Bhudolia 1,2,* , Goram Gohel 1,2 , Kah Fai Leong 1,2 and Aminul Islam 3,* 1 School of Mechanical and Aerospace Engineering,
    [Show full text]
  • Automated Aerial Seed Planting Using Biodegradable Polymers
    http://researchcommons.waikato.ac.nz/ Research Commons at the University of Waikato Copyright Statement: The digital copy of this thesis is protected by the Copyright Act 1994 (New Zealand). The thesis may be consulted by you, provided you comply with the provisions of the Act and the following conditions of use: Any use you make of these documents or images must be for research or private study purposes only, and you may not make them available to any other person. Authors control the copyright of their thesis. You will recognise the author’s right to be identified as the author of the thesis, and due acknowledgement will be made to the author where appropriate. You will obtain the author’s permission before publishing any material from the thesis. Automated Aerial Seed Planting using Biodegradable Polymers A thesis submitted in fulfilment of the requirements for the degree of Masters of Engineering in Mechanical Engineering at The University of Waikato by Wade Cozens 2019 The purpose of the thesis was to undertake a preliminary product design to assess the feasibility of using drone technology to aid reforestation for automated seed planting. This product would be able to increase productivity and reduce labour costs, especially when applied in difficult to reach terrains around New Zealand. Ultimately, the final product would be a weaponised drone or a swarm of drones that can fire plastic seed capsules into soil to a specific depth to prevent predation and ensure optimal germination conditions. The proof of concept hinges on the success of three objectives: Assessing and controlling the capsule’s biodegradability in soil.
    [Show full text]
  • Plastic Welding Certification Process Executive Summary
    Plastic Welding Certification Process Executive Summary Foresight Technologies (US) and Foresight Asia Pacific Sdn. Bhd. (Malaysia) are global leaders in precision CNC machining, plastic welding and high purity assembly. With a combined staff of 250 employees, 50+ CNC machine tools and 30 Certified Plastic Welders, Foresight strives to be the preferred supplier and collaborative partner of our customers. As a provider of critical plastic systems to semiconductor, aerospace and chemical equipment markets, we struggled fitting the somewhat “Artisan Craft” of plastic welding into our process driven quality systems. We understand the criticality of the chemical systems; any leak could expose operators to unsafe conditions, cause significant downtime for wafer fabs, and potentially damage millions of dollars of product. While plastic welding has many applications, in the semiconductor industry it has an additional cosmetic requirement which conflicts with many of the standard certifications. Not only must the weld be strong, it must also have minimal pits, capillaries and fluctuations in wake flow. These cosmetic imperfections can provide dead spots where bacteria and contaminants can accumulate, and this can have a major impact on wafer device performance and yield. This white paper looks at Foresight’s process of plastic welding certification, industry standards that provide the framework for plastic welder certification and explains the necessity of repeating these processes and ensuring that they meet process requirements of advanced quality OEMs. 2 Plastic Welding Certification Process Foresight’s History of Plastic Welding Years ago, Foresight recognized the wide variability in plastic welding quality, even among 20-year veterans of the trade. Everyone had their own process and unfortunately, this caused variability in the final product.
    [Show full text]
  • Joining of Nylon's Based Plastic Components
    BASF Corporation JOINING OF NYLON BASED PLASTIC COMPONENTS -- VIBRATION AND HOT PLATE WELDING TECHNOLOGIES Abstract mechanical properties. Molded nylon parts are more resistant to creep, fatigue, repeated impact, Previously we reported to SPE’96 the and so on compared to the parts made of many optimized mechanical performance of linear less rigid thermoplastics. vibration welded nylon 6 and 66 butt joints. Under the optimized vibration welding There are more than a dozen classes of conditions (amplitude, pressure, meltdown, nylon resins, including nylon 6, nylon 66, nylon thickness of interface), the tensile strength at the 46, nylon 12, etc.). Welded nylons are used in nylon butt joints was equal to or 14% higher than many industrial products, the largest being the the tensile strength of the base polymer (matrix). automotive. In recent years, demands to use non-filled, fiber-glass reinforced and filled nylon H. Potente and A. Brubel presented to products to replace metals and thermosets in SPE’94 and SPE’98 an analysis of the welding power tools, lawn / garden equipment (leaf performance in a family of amorphous and semi- blowers, chain-saws, gas-tanks), and the crystalline thermoplastics including nylon 6 automotive (air induction, power train systems, using hot-plate welding technologies. For hot- fluids reservoirs, and other uses), have increased plate welded nylon 6 with a range of glass-fiber (1, 2). reinforcement from 0 to 40% (by weight), the tensile strength at the weld was 40–60% less On average a car uses 18 kg of nylon compared to the tensile strength of the base based plastics.
    [Show full text]
  • Starting out in Plastic Welding
    Starting out in Plastic Welding Most all plastics can be joined using mechanical means (e.g., screws) and with cements and adhesives (e.g., PVC cement). Thermoplastics--plastics that become soft when heated--can also be welded using a non-flame heat source. Examples of thermoplastics include • PVC (polyvinyl chloride) • Polypropylene • ABS (acrylonitrile Butadiene Styrene) • Nylon • Vinyl • Acrylic • Polyethylene • Polycarbonate • Acetal resin • Polystyrene There's another class of plastics that don't become soft when heated--once they're set, that's it. These thermosetting plastics can't be welded. Examples include phenolic, polyester, silicone, and epoxy. To hot-gas weld plastic, air or an inert gas is heated to between 450°F and 800°F. The gas is heated by an electric element rather than a flame. A filler rod of the same material as the pieces to be joined is heated along with the joint, and the filler rod is lightly pressed into the joint (see figure on back). Torches sometimes include a special nozzle that both preheats the filler rod and guides it into the joint. Plastic can also be welded using a heated tool, induction welding, or friction (spin) welding. Hot gas plastic welders are available from several sources, but often at high prices (e.g, $326 for the low-end Kamweld model). Harbor Freight sells one for $39.99 (item 41592-1VGA), often on sale for $29.99. It includes the torch, air hose, regulator, stand, and a small selection of filler rod for PVC, polypropylene, and ABS. The “trick” to using a hand-held hot air plastic welder seems to be in part to get the temperature right.
    [Show full text]
  • Welding of Infrared Transmissive Thermoplastic Polymers Using Diode Laser Systems
    Welding of Infrared Transmissive Thermoplastic Polymers using Diode Laser Systems Scott Hartley and Nicole Woosman Gentex Corporation, 324 Main Street Carbondale, PA 18407 USA Abstract Clearweld™ technology is a tool, which is readily employed for transmission laser welding of thermoplastic polymers using near infrared diode lasers. This process is accomplished through the use of specialized material systems uniquely chosen and targeted to absorb the laser light at the intended laser weld joint in order to rapidly effectuate a weld. Data will be presented showing actual weld strengths, critical process parameters, and quantification of residual stresses in a variety of thermoplastic materials. Keywords: polymer joining, plastics welding, laser transmission welding, laser materials processing, laser materials processing, Clearweld 1 Introduction The principal disadvantage of laser welding has been the need to use carbon black as an absorbent, posing a Transmission laser welding involves the use of high- limitation in applications where appearance and color density electromagnetic energy produced by a laser are important. source to create thermal energy at the joint interface necessary for weld formation. Plastics in their natural 2 The Clearweld™ Process state do not absorb near-infrared (NIR) light; therefore energy from lasers operating in the NIR efficiently A significant process advancement has been developed transmits through plastics. To successfully use lasers that offers all the advantages of conventional laser for joining polymer, this laser energy must be properly welding without the use of opaque materials or the harnessed to create the heating and intermolecular addition of unwanted color. The process can be used to diffusion critical for weld formation.
    [Show full text]
  • Master Proheat® Plastic Welding Kit Manual
    MASTER PLASTIC WELDING ROD REORDER INFORMATION 35297 ABS Welding Rod (Pkg. of 16) Round, 1/8” Dia. x 9” Long, Natural, for welding ABS plastics MASTER PROHEAT ® 35298 PP Welding Rod Plastic Welding Kit (Pkg. of 16) Round, 1/8” Dia. x 9” Long, Natural, for welding PP plastics 35299 PVC Welding Rod (Pkg of 16) Round, 1/8” Dia. x 9” Long, Grey, for welding PP plastics 35300 LDPE Welding Rod (Pkg of 16) Round, 1/8” Dia. x 9” Long, Natural, for welding LDPE plastics 35301 HDPE Welding Rod (Pkg. of 16) Round, 1/8” Dia. x 9” Long, Black, for welding HDPE plastics MSDS Sheets available upon request. Warning: These products contain chemicals known to the State of California to cause Welding Plastics with the cancer and birth defects or other reproductive harm. Users should independently evaluate the suitability of the product for their application. MASTER PROHEAT ® Model PH-1400WK Master Appliance Corp. 2420 18th St. Professional Quality Electronic Heat Gun Racine, WI 53403 USA Plastic Welding Kit Tel: 1-800-558-9413 (toll free in the U.S.A. and Canada) Tel: 262-633-7791 (all other Countries) Fax: 262-633-9745 Email: [email protected] www.masterappliance.com P/N 58053 REV A © 2010 Master Appliance Corp. PLASTIC WELDING MASTER PROHEAT ® Plastic Welding Kit Basic requirements for plastic welding. TIME, TEMPERATURE & PRESSURE PH-1400WK Most plastics used today are thermoplastics, which are generally suitable for repair by welding. Four basic rules for plastic welding are suggested: 1. Weld with like material. Only like materials can be welded, i.e.
    [Show full text]