Technical Guidebook. - Polyglycolic Acid (PGA) - KUREHA CORPORATION KUREHA AMERICA LLC. KUREHA GmbH. KUREHA (SHANGHAI) Co., Ltd.

Transcription

1 The Pursuit of Excellence - Polyglycolic cid (PG) - Technical Guidebook KUREH CORPORTION Nihonbashi-Hamacho, Chuo-Ku Tokyo, Japan Tel: KUREH MERIC LLC 420 Lexington ve., Suite 2510 New York, NY , U.S.. Tel: KUREH (SHNGHI) Co., Ltd Gangtai Plaza, 700 Yanan East-Road Shanghai, People s Republic of China Tel: KUREH GmbH Liesegangstrasse Dusseldorf, Germany Tel:

2 Contents 1. General Information 1.1 What is Kuredux? 1.2 Kuredux grades 2. Characteristics of Kuredux 2.1 Basic properties 2.2 Mechanical properties 2.3 Thermal properties 2.4 Barrier properties 2.5 Optical properties 2.6 Electrical properties 2.7 Chemical resistance 2.8 Biodegradation 2.9 Melt behavior 3. Kuredux Processing Information 3.1 Handling precautions 3.2 Extrusion 3.3 Injection molding 3.4 Secondary processing 4. Kuredux Regulation Compliance and Certifications

3 1. General Information 1.1 What is Kuredux? Kuredux is a registered trade mark of Kureha Corporation for its semi-crystalline polyester polyglycolic acid (PG) resin. Kuredux has the simplest molecular structure among aliphatic polyesters (Figure 1-1) and is characterized by: Excellent gas barrier High mechanical strength and toughness Biodegradability / Hydrolysis Easy processing O CH 2 C O Fig.1-1 Molecular structure of Kuredux Film, Bottles n 2. Characteristics of Kuredux 2.1 Basic Properties Density Kuredux is a high-density material, with a specific gravity of 1.50g/cm 3 in the amorphous state and 1.70g/cm 3 in the crystalline state (Table 2-1). Kuredux s maximum degree of crystallinity is approximately 50%. Table 2-1 Density of Kuredux Density [g/cm 3 ] Kuredux 1.50 ~ 1.60 PET 1.34 ~ 1.45 PL 1.25 ~ 1.29 Data sources: Hideto Tsuji, Science of Biodegradable Polymer Materials, Corona, 2002 High gas barrier Biodegradable Hydrolytic PVT Curve The relationship between pressure, volume and temperature of Kuredux is shown in Figure 2-1. Industrial materials High Strength Fig.1-2 Characteristics of Kuredux Fibers Specific volume [cm 3 /g] MPa 20MPa 40MPa 80MPa 120Mpa 160MPa 1.2 Kuredux Grades There are three grades of Kuredux resin commercially available (Table 1-1). Table 1-1 Kuredux grades Temperature[ C] Fig. 2-1 PVT curves of Kuredux Kuredux 100E35 Kuredux 100R60 Kuredux 100T60 Base grade Hydrolysis resistant grade Hydrolysis resistant grade for bottle applications Note: pplications for Kuredux100T60 are not limited to bottles

4 2.2 Mechanical Properties Injection Molding Mechanical properties of Kuredux injection molded specimens are shown in Table 2-2. Kuredux exhibits high mechanical strength and modulus, which are equivalent to or even exceed those of engineering plastics. 2.3 Thermal Properties Thermal Properties Thermal properties of Kuredux are summarized in Table 2-5. Table 2-5 Thermal properties of Kuredux Test method Unit Kuredux Table 2-2 Mechanical properties of Kuredux injection molded specimens Test method Unit Kuredux Tensile strength ISO 527-1,2 MPa 117 Melt temperature (Tm) ISO Glass transition DSC method temperature (Tg) Heating rate: Cold crystallization 20 C/min temperature (Tc) C 220 C 40 C 95 Tensile elongation ISO 527-1,2 % 13 Coefficient of linear thermal expansion ISO (1.82MPa) 1/K Flexural modulus ISO 178 GPa 7.6 Heat deflection temperature ISO 75 C 168 Flexural strength ISO 178 MPa 195 Thermal conductivity ISO 8302 W/m K 0.35 Film Charpy impact strength Izod impact strength Rockwell hardness ISO 179 kj/m ISO 180 J/m 29.2 ISO M scale 111 Kuredux s mechanical strength and modulus increase significantly as a result of molecular chain orientation. Mechanical properties of un-oriented film and oriented film are shown in Tables 2-3 and 2-4. Table 2-3 Mechanical properties of Kuredux un-oriented film Test method Unit Kuredux Tensile modulus ISO GPa 3.3 Tensile strength ISO MPa 113 Tensile elongation ISO % 5 Film thickness: 100µm Table 2-4 Mechanical properties of Kuredux oriented film *Calculated by % elongation Test method Unit Kuredux Tensile modulus MD ISO GPa 7.0* TD 5.5* Tensile strength MD ISO MPa 380 TD 250 Tensile elongation MD ISO % 40 TD 80 Film thickness: 20µm Stretch ratio: MD5.0, TD3.5 In Figure 2-2 below, heat deflection temperatures (HDT) of Kuredux are compared. Kuredux natural grade has an HDT of 168 C and has heat resistance for over 40 C, beyond its Tg. HDT of Kuredux further improves up to nearly its crystalline melt point if enhanced with glass fiber, etc. HDT(GF30%)[ ] Crystalline polymer Noncrystalline polymer PET POM PPS MXD6 Kuredux PC PEEK P R PEO P I Fig. 2-2 Heat deflection temperature of Kuredux Energy on Combustion HDT(unreinforced)[ C] Energy released by combusting Kuredux is shown in Table 2-6. Kuredux requires relatively low combustion heat, imposing less incineration burden. Table 2-6 Energy on combustion for Kuredux Energy on combustion [kj/g] Kuredux 12 PLL 19 PE 46 PET 23 P 31 POM 17 PC 31 Data sources: Plastics Data Handbook 1988, etc PI

5 2.4 Barrier Properties Gas Barrier Properties Kuredux demonstrates excellent barrier against various gases such as O 2, CO 2, N 2 and moisture vapor and is one of the top barrier materials commercially available today. Barrier properties of Kuredux are shown in Table 2-7 and Figure 2-3 below. Table 2-7 Barrier properties of Kuredux OTR CO 2 TR WVTR Test method Unit Kuredux ISO (23-80%RH) ISO (23-80%RH) ISO (40-90%RH) cm 3 /m 2 /day/atm (20µm) g/m 2 /day (20µm) Flavor / roma Retention Kuredux demonstrates a high retention rate for commonly used flavor and aroma groups as shown in Table 2-8. Kuredux is suitable for packaging which requires flavor/aroma preservation for a prolonged period of time. Table 2-8 roma/flavor retention of Kuredux Film thickness [µm] (Test condition: 30 C-50%RH) d-limonene L-Menthol Vanillin Kuredux EVOH 16 C PVDC 10 C C C 10 3 P6 +: No failure after 2 weeks B : Failure after 1 week : Failure after 2 weeks C: Failure after 3 days (Results of lab evaluation using Kureha original test method) WVTR [g/m²/day] 40 C-90%RH, 20µm Kuredux EVOH (32mol%) MXD6 PET PVDC P12 LDPE PP Organic Vapor Barrier Kuredux exhibits superior barrier performance against organic vapors as shown in Table OTR [cm³/m²/day/atm] 30 C-80%RH, 20µm Fig. 2-3 OTR and WVTR of Kuredux Relative Humidity[%] Table 2-9 Organic vapor barrier of Kuredux (Unit: mg/m 2 /day/kpa,film thickness: 10µm) Kuredux EVOH(32mol%) PET Humidity-Independent Barrier Performance Toluene 50 C Kuredux barrier properties are not impacted by high relative humidity conditions as are other common barrier materials (Figure 2-4). OTR [cm³/m²/day/atm] 23 C, 20µm Kuredux MXD6 EVOH 32mol% cetone 30 C Ethanol 30 C (Results of lab evaluation using Kureha original test method) Relative Humidity [%] Fig. 2-4 Humidity Sensitivity of Kuredux

6 2.5 Optical Properties Optical Properties Kuredux has a high total luminous transmittance rate (Table 2-10). UV Transmission Kuredux demonstrates a high transmission rate for ultraviolet (UV) rays in the shorter wavelength region, as shown in Figure 2-5. Transmission rate [%] 100 Table 2-10 Optical properties of Kuredux film Total luminous transmittance [%] Un-oriented film (morphous) 110µm Un-oriented film (Crystalline) 110µm Oriented film 8µm Haze [%] Un-oriented film (morphous) 110µm Un-oriented film (Crystalline) 110µm Oriented film 8µm Refractive index [nd 23 ] Un-oriented film (morphous) 110µm Un-oriented film (Crystalline) 110µm Oriented film 8µm Test method Kuredux ISO ISO ISO Kuredux 100µm PET 200µm 20 PMM 100µm PC 250µm Wavelength [nm] Fig. 2-5 Ultraviolet visible absorption spectra of Kuredux < < Electrical Properties Table 2-11 shows electrical properties of Kuredux. Kuredux demonstrates high dielectric constant and dielectric loss tangent, which are higher than those of standard insulation materials. Table 2-11 Electrical properties of Kuredux Test method Unit Kuredux Surface resistance IEC Ω/sq Volume resistance IEC Ω cm Dielectric constant 1MHz Dielectric loss tangent 1MHz 2.7 Chemical Resistance Chemical Resistance Solvents for Kuredux IEC IEC Kuredux has high chemical resistance against various substances (Table 2-12). Table 2-12 Chemical resistance of Kuredux Hexane Cyclohexane Carbon tetrachloride Xylene Toluene Ethyl cetate Tetrahydrofuran Chloroform Methylethyl ketone Methylene chloride cetone Isopropyl alcohol N,N-dimethylformamide Ethanol Methanol Kuredux Kuredux has high chemical resistance and is not soluble in most solvents. However, the following three solvents are known to be applicable for Kuredux. B B C C : Weight change less than 0.1% B: Weight change between 0.1~1% C: Weight change over 1% Test method: Kuredux sheet (10X40X2mm) was immersed in each chemical substance and stored at 23 C for seven days before measuring sheet weight change. C B HFIP (Hexafluoroisopropanol) High-temperature DMSO(Dimethyl sulfoxide) High-temperature NMP(N-Methylphyrrolidone)

7 2.8 Biodegradation Biodegradability Kuredux is a biodegradable resin and degrades into CO 2 and water in compost within one month*. The resultant compost has been proven safe. Kuredux has been certified as a biodegradable plastic in Japan, Europe and the US. *Degradation rate is largely affected by the condition of compost and differs in the range of 30 to 90 days. Europe US Japan Fig. 2-6 Certifications for biodegradability of Kuredux Biodegradation [%] Fig. 2-7 Biodegradability of Kuredux and Cellulose Hydrolysis (Tested on ISO protocols) Kuredux degrades relatively quickly when in contact with water, making it useful as a temporary masking material or core molding material. Figure 2-8 shows the degradation rate of Kuredux in water at a temperature of 60 C. Note that the degradation rate tends to increase in higher temperatures or in alkaline environments Time [days] Cellulose Kuredux * Tested under aerobic conditions maintained at 58 in controlled compost 2.9 Melt Behavior Melt Properties The melt viscosity of Kuredux in different share rates and temperatures is shown in Figures 2-9 and 2-10 respectively. Melt viscosity [Pa sec] Kuredux 100R Fig. 2-9 Melt viscosity vs. shear rate of Kuredux Melt viscosity [Pa sec] at 122sec Shear rate [sec -1 ] Kuredux 100E35 Kuredux 100R Temperature [ ] Fig Melt viscosity vs. temperature of Kuredux Mass retention [%] PL Kuredux Time [days] Fig. 2-8 Hydrolytic degradability of Kuredux and PL Test method: Particles of Kuredux and PL (approx. 100µm in diameter) were submerged in 60 C water and the weight retention rate was measured.

8 3. Kuredux Processing Information 3.1 Handling Precautions for Kuredux Kuredux can be readily processed on conventional primary processing equipment. Subsequent conversion of Kuredux via thermoforming, lamination and other downstream processes to final end-products has been demonstrated under standard operating conditions. Kuredux is also used as an additive to enhance the performance of other polymers or incorporate new properties. Figure 3-1 shows some examples of Kuredux applications. Before use Kuredux is hydrolytic and begins degrading when exposed to humidity. The resin has been pre-dried and packaged in moisture-proof bags and is ready to use when delivered. However, for extrusion and other molding processes, it is recommended to pre-dry the resin before use in order to insure its original properties and molding stability. Primary Processing Secondary Processing Extrusion (mono-/multi-layer) Injection molding Thermoforming Lamination Biaxial stretch molding (mono-/multi-layer) (pplication examples) Film, Sheet, Fibers, Nonwovens Multi-layer preforms, Molded parts Cups, Trays Film, Sheet Film During processing It is desirable to use a molding machine equipped with a hopper dryer which prevents moisture absorption of Kuredux. However, the same drying effects can be obtained by making dry air flow constantly through the process. If the resin is not sufficiently dried and processed, it may have lower viscosity and/or exhibit heat degradation, possibly resulting in defective production. Do not keep the molten resin at elevated temperatures for prolonged periods of time. Clean extruders and injection molding machines thoroughly post production, in order to avoid adherence and corrosive damages to the machinery. Stretch blow molding (mono-/multi-layer) Bottles fter use It is recommended that all resin be consumed once the bag is opened. Partially used bags must be sealed and stored in a cool, dry environment. ll subsequent use requires re-drying in order to insure original resin properties. Recommended drying condition is 120 C for 12 hours (with dry air at a dew point of -40 C), not to exceed 24 hours. It is not recommended to use any resin which was left exposed to humidity for prolonged periods of time (i.e., resin left unused for 4 hours in 23 C 60%RH conditions or resin whose moisture content measures a few hundred ppm) Disposal of any used or unused resin must be in compliance with federal, state and local environmental control regulations. Fig. 3-1 Examples of Kuredux applications Kuredux can be co-molded with various polymers. Figure 3-2 indicates typical molding temperatures for Kuredux. Please read the Material Safety Data Sheet for more details regarding the proper handling of Kuredux. 350 Molding temperature [ C] Kuredux POM P6 PET PP PS HDPE PL Fig. 3-2 Range of molding temperatures for Kuredux

9 3.2 Extrusion Kuredux can be extruded or co-extruded on most conventional equipment (T-die, circular die, etc). Screw design full-flight screw is recommended to use for Kuredux. However, a screw having a long compression zone and/or high compression ratio is not recommended. Molding temperatures Table 3-1 shows recommended extrusion temperatures for Kuredux. Kuredux resin should not be processed at temperatures above 280 C due to possible thermal degradation. Table 3-1 Recommended conditions for extruding Kuredux Feeding zone 220 ~ 240 C 3.3 Injection Molding Screw design full-flight screw having low compression ratio is recommended for Kuredux. Molding temperatures Table 3-2 shows typical injection molding conditions for Kuredux. Table 3-2 Typical conditions for injection molding Kuredux Cylinder temperature 230 ~ 270 Mold temperature 100 ~ 120 Injection pressure Injection speed 50 ~ 100MPa 2-3m/min *Conditions for injection molding STM compliant family mold test piece on a machine with 75ton-locking pressure Compression zone Metering zone dapter, Die 230 ~ 260 C 250 ~ 270 C 240 ~ 270 C Cylinder temperatures Targeted cylinder temperatures are within the range of 230 and 250 C as shown in Figure 3-3. They should not exceed 280 C to ensure optimal properties of Kuredux. Start-up, Shut-down, Purging Metering zone Feed zone Torpedo Compression zone Start-up (after extruder reaches its pre-set temperature) Prior to introducing Kuredux into any extruding system, the system should be thoroughly cleaned with commercial purging materials (polypropylene, polyethylene, etc.) Insure the system is free of any residual polymers, particularly polyesters, polyalcohols and polyamides, due to their possible chemical reaction with Kuredux. Shut-down Turn off extruder after removing Kuredux thoroughly with commercial purging materials (polypropylene, polyethylene, etc.) It is recommended to disassemble and clean extruders periodically to ensure optimal operation of the machinery. Emergency shut-down Kuredux is susceptible to heat degradation if exposed to prolonged high temperatures. In case of unexpected shut-down while Kuredux is in use, it is recommended to purge the extruder promptly. H1 250 C H2 250 C H3 220 C H4 200 C Figure 3-3 Sequential cylinder temperatures Mold temperature Targeted mold temperatures are in the range of 100 to 120 C. They should not exceed 120 C to avoid mold shrinkage. Injection pressure Injection pressure of MPa is recommended for Kuredux. Normally lower pressure is preferred to avoid generating flashes. Back pressure Targeted back pressure should be in the range of 0 to 1.0MPa in order to stabilize metering quality. dhesives n adhesive resin may be necessary when Kuredux is co-extruded with other materials. The following adhesive resin is recommended to use for Kuredux : MODIC (Mitsubishi Chemical Corporation) Co-injection molding for multilayer PET preforms For PET/Kuredux multilayer preforms, a co-injection molding machine is recommended which can separately control molding temperatures for Kuredux and PET layers. (e.g., hot runner mold system by Kortec Inc.) Recommended co-injection molding temperatures are: Cylinder: Hot runner:

10 3.4 Secondary Processing Stretch molding temperatures Kuredux can be stretch molded at over 45 C. Figure 3-4 shows typical processing temperatures for Kuredux monolayer film and multi-layer(ml) films with other polymers. Table 3-3 Blow molding conditions for Kuredux multi-layer preform* vs. PET monolayer preform* PET monolayer PET/Kuredux /PET multilayer Temperature[ ] Monolayer P/Kuredux ML PE/Kuredux ML PET/Kuredux ML Over all [%] Z5 [%] 42 off Z4 [%] Z3 [%] Z2 [%] Z1 [%] PL/Kuredux ML Figure 3-4 Kuredux stretch molding temperatures Stretch properties Figure 3-5 shows stretchability of Kuredux monolayer and multi-layer films. Preform temperature [ C] Low blow position [deg] Low blow pressure [MPa] High blow position [deg] Monolayer film Stretch ratio High blow pressure [MPa] *Conditions for 20g preform for 360ml pressure bottle Multi-layer film Fig. 3-5 Stretchability of Kuredux films Stretch blow molding Figure 3-6 and Table 3-3 indicate optimal stretch ratio and blow molding conditions for PET/Kuredux /PET multi-layer preform. Useful tips for stretch blow molding multilayer bottles (vs. PET monolayer) Set the timing of pre-blow earlier Set preform surface temperature after pre-heating at 5-10 C higher Slightly increase heat power for preform neck parts (Z1 and Z2) djust heat power to control base weight for preform base parts Recommended stretch ratio: L2/L1=2.5 (less than 2.7) L2/L1XD2/D1=12.5 Lamination Kuredux can be laminated onto various materials, including PET, polyethylene, polypropylene, polylactic acid, and aluminum. Use of two-component type urethane adhesives is recommended. Thermoforming D1 L1 D2 L2 Kuredux can be thermoformed in combination with PET, polypropylene, polylactic acid, etc. Recommended forming temperatures are generally in the range of 70 to 110 C. Optimal forming temperatures differ depending on layer structures. L1: Length of preform D1: Inside diameter L2: Length of bottle D2: Outside diameter Figure 3-6 Recommended stretch ratio for PET/Kuredux multi-layer preform

11 4. Regulation Compliance and Certifications Table 4-1 shows the current status of Kuredux regulation compliance as well as certification approval. Table 4-1 Kuredux Regulation Compliance and Certifications ct on the Evaluation of Chemical Substances and Regulation of Their Manufacture, etc Japan The Council for PET Bottle Recycling Japan BioPlastic ssociation (JBP) GreenPla Positive List Toxic Substances Control ct (TSC) US FD/FCN No. 958 No. 574 (part of 958) Biodegradable Products Institute (BPI) Compostable The European Inventory of Existing Commercial Chemical Substances (EIENECS) EU Registration, Evaluation, uthorization and Restriction of Chemicals (RECH) EU Regulation (EU) No 10/2011 VINCOTTE OK Compost (s of pril 2011) Kuredux is not intended for use in biomedical applications. For biomedical applications, contact your Kureha representative for information on Kuresurge PG ll data contained in this bulletin are results of measurement and not secured values. Kureha Corporation assumes no liability of absolute accuracy and completeness of presented information. Contact us for further information on Kuredux and its usage and suitability for your products.

12 The Pursuit of Excellence