Calcium Carbonates for Sealants. Redefining Performance. Kalena Stovall, PhD Imerys Carbonates. October 19, 2016

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1 Calcium Carbonates for Redefining Performance Kalena Stovall, PhD Imerys Carbonates October 19, 2016

Calcium Carbonates in Caulks and sealants use high levels of calcium carbonate for desired performance and cost reduction Reactive sealants often need very low moisture content for processing and

2 Calcium Carbonates in Caulks and sealants use high levels of calcium carbonate for desired performance and cost reduction Reactive sealants often need very low moisture content for processing and shelf stability Specialty engineered carbonates are incorporated to control rheology and mechanical properties Higher brightness calcium carbonates offer better color match and surface finish Typical carbonates in caulks and sealants Water-borne caulks: medium PSD GCC Reactive sealants: fine PCCs and GCCs, treated carbonates 10/19/2016

GCC and PCC Manufacturing Ground Calcium Carbonate (GCC)

Grind 2.5 and smaller pebbles 1 mm and smaller (0.

Aragonite, Calcite Big rock Pebble Powder Final powders

by nature and processing Chemically prepared in aqueous

options than GCC Purer calcium carbonate than most GCCs

3 GCC and PCC Manufacturing Ground Calcium Carbonate (GCC) Precipitated Calcium Carbonate (PCC) Crush, Pulverize, Grind 2.5 and smaller pebbles 1 mm and smaller (0.4 µm) particles Ultrafine PCC Polymorphs: Vaterite, Aragonite, Calcite Big rock Pebble Powder Final powders made by wet or dry grinding Calcite, only Purity impacted by nature and processing Chemically prepared in aqueous solution Multiple polymorphs and crystal shapes Finer PSD options than GCC Purer calcium carbonate than most GCCs Higher surface area than GCC Can surface treat either product (with fatty acid or other) 3 10/19/2016

4 All Calcium Carbonates Are Not the Same.. 10/19/2016

5 Typical Differentiation Properties between PCC and GCC Particle or granular size Morphology / aspect ratio Brightness Surface functionality Chemical purity Moisture content Surface area Porosity Oil absorption Silicone and modified silicones Polyurethane and silane-terminated Water-borne Acrylics Polysulfide Butyl Cost Manufacturing cycle Package stability Application Adhesion Tensile properties Chemical resistance 5 10/19/2016

% pass Particle Size Distribution: More than d50 Matters (Example 3 µm GCCs) 100 3 µm untreated GCC 3 µm fatty acid treated GCC 1 3 µm fatty acid treated GCC 2 3 µm GCC treated with engineered

6 % pass Particle Size Distribution: More than d50 Matters (Example 3 µm GCCs) µm untreated GCC 3 µm fatty acid treated GCC 1 3 µm fatty acid treated GCC 2 3 µm GCC treated with engineered treatment Particle Diameter (µm) Treated GCC 1 and untreated GCC contain more fines may be higher surface area GCC may have higher viscosity sealant Fines can be viewed two ways: 1. Overall steepness of the curve more steep = less fines = likely lower viscosity/ faster extrusion rate 2. % of particles passing at 1 µm 6 10/19/2016

% pass Particle Size Distribution: More than d50 Matters (Example PCCs) 100 Treated PCC, PPS: 0.06 µm Treated PCC, PPS: 0.06 µm Treated PCC, PPS: 0.07 µm Treated PCC, PPS: 0.

7 % pass Particle Size Distribution: More than d50 Matters (Example PCCs) 100 Treated PCC, PPS: 0.06 µm Treated PCC, PPS: 0.06 µm Treated PCC, PPS: 0.07 µm Treated PCC, PPS: 0.1 µm Particle Diameter (µm) PSD curve and primary particle size (PPS) in PCCs should be considered together available surface area sealant rheology, mechanical properties Inflections of particle sizes in a single batch particle packing in sealant and sealant viscosity 7 10/19/2016

8 Calcium Carbonate Differentiation Study 8 10/19/2016

9 Calcium Carbonate Differentiation Looking Beyond PSD Known: PSD and moisture content can influence sealant performance Manufacturers use untreated and treated GCC, PCC or both to optimize sealant properties Curiosity/ Hunch: Surface area and surface treatment impact sealant: Processing time Rheology Mechanical properties To probe this, tested GCCs of varying surface area and surface treatment in a SPUR construction sealant Fixed GCC PSD at 3 microns, and examined: GCC Surface Treatment Surface Area Untreated Naked surface High surface area Classically treated Excess carboxylic acid* Low surface area Classically treated Excess carboxylic acid* Low surface area Engineered product No excess treatment Medium surface area *Classical carbonate treatment to obtain a monolayer of fatty acid coverage typically yields an excess of unreacted carboxylic acid 9 10/19/2016

10 SPUR Sealant Formulation SPUR Sealant Formulation Component Wt % SPUR+ 1015LM prepolymer 22.2 Plasticizer (DIDP) 18.5 Moisture scavenger (Silquest A-171* silane) 1.0 Calcium Carbonate (PCC) 30.0 Calcium Carbonate (GCC) 25.5 UV Stabilizers 0.5 Thixatropic Agent (SiO2) 0.2 Colorant (TiO2) 1.2 Adhesion Promoter (Silquest* A-1110 silane) 0.6 GCCs and PCCs Tested Product PPS, µm Treatment level, wt % GCC A GCC B GCC C GCC D PCC PCC PCC PPS = primary particle size Surface Area, m 2 /g Catalyst (dibutyltin dilaurate) /19/2016

11 Calcium Carbonate Influence on Silylated Polyurethane (SPUR) Sealant Pre-Batch Processing Time 11 10/19/2016

12 Calcium Carbonate Influence on SPUR Sealant Pre-Batch Processing/ Drying Time Pre-batched GCC and PCC with DIDP, TiO 2 and anti-oxidant package GCC and PCC not pre-dried Compounded in mixer with high speed disperser blade (1000 rpm) and scraper blades (60 rpm) Mixed under vacuum at 93C until 800 ppm reached Time to reach 800 ppm tracked Moisture level checked using volumetric Karl Fisher titration 12 10/19/2016

13 Sealant Initial Moisture (ppm) Time to Reduce Moisture to 800 ppm (mins) Calcium Carbonate Influence on Pre-Batch Processing/ Drying Time GCC surface area (m 2 /g): PCC surface area (m 2 /g): S e GCC A PCC 1 GCC D PCC 3 GCC B PCC 2 GCC C PCC 1 Pre-batch processing target: 800 ppm moisture Surface area is not the clear influencer 13 10/19/2016

14 Sealant Initial Moisture (ppm) Time to Reduce Moisture to 800 ppm (mins) Calcium Carbonate Treatment Influences Pre-Batch Processing/ Drying Time GCC treatment: 1 None 2 Fatty Acid 3 Fatty Acid 4 Engineered Treatment Unreacted Treatment (wt%): 0 n/a 0.4 GCC A PCC 1 GCC D PCC 3 GCC B PCC 2 0 GCC C PCC S e Pre-batch processing target: 800 ppm moisture Engineered treatment reduces processing/drying time compared to traditionally treated carbonates 14 10/19/2016

15 Calcium Carbonate Influence on SPUR Sealant Rheology & Mechanical Properties 15 10/19/2016

SPUR Sealant Rheology Sealant based on SPUR+

Compounding Extrusion rate Semco nozzle,

16 SPUR Sealant Rheology Sealant based on SPUR+ 1015LM prepolymer compounded with GCC and PCC Rheology: Extrusion rate/ gunnability (ASTM C1183) Slump (ASTM D2202) Brookfield viscosity Mixing / Compounding Extrusion rate Semco nozzle, cartridge, instrument 40 psi, mm nozzle tip Slump 16 10/19/2016

17 Extrusion Rate (g/min) Influence on Extrusion Rate k cp 373k cp 329k cp 290k cp Brookfield Viscosity GCC surface area (m 2 /g): PCC surface area (m 2 /g): GCC treatment: None Fatty Acid Fatty Acid GCC A PCC 1 GCC D PCC 3 GCC B PCC 2 Engineered Treatment GCC C PCC 1 In general, higher GCC surface area higher Brookfield viscosity and lower extrusion rate Having no unreacted treatment may influence rheology differently 17 10/19/2016

18 SPUR Sealant Mechanical Properties SPUR sealant cured for 2 weeks at 23C and 50% RH Mechanical Properties: Tensile (ASTM D412) Tear (ASTM D624) Tensile Testing Tear, Die B 18 10/19/2016

19 Influence on Mechanical Properties (Medium Modulus Sealant) % Break Break, psi GCC surface area (m 2 /g): PCC surface area (m 2 /g): GCC treatment: Fatty Acid Fatty Acid None GCC A PCC 1 GCC D PCC 3 GCC B PCC 2 Engineered Treatment GCC C PCC 1 Increase elongation for similar tensile behavior using treated GCC As-good-as or better tensile performance with untreated GCC versus treated GCC 19 10/19/2016

20 Summary Surface area and surface treatment DO impact sealant processing time, rheology, and mechanical properties Specifically, Surface treatment Processing time Surface area Rheology Surface treatment Mechanical properties and rheology Engineered product provides: Lower processing and drying time Good mechanical properties Rheology modification 20 10/19/2016

21 Thank you for your attention For more information, visit:

SPUR+* 1015LM. Technical Data Sheet SPUR+* 1015LM

SPUR+* 1015LM. Technical Data Sheet SPUR+* 1015LM Technical Data Sheet SPUR+* 1015LM SPUR+* 1015LM Description SPUR + 1015LM prepolymer is a silylated polyurethane resin for manufacturing one-part, moisture-curing sealants and adhesives. Plasticizer-free