HK Research MaxGuard NP White Marine ISO/NPG Gelcoat vs. Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester
HK Research MaxGuard NP White Marine ISO/NPG Gelcoat (HK Research Corp) and Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester (Interplastic Corp) achieve a 68% ASTM engineering compatibility score in Marine ISO/NPG Gelcoats, Structural Bonding Pastes & Mold Releases. Tensile strength delta is +6 MPa (+9.1%) and thermal HDT delta is +13 °C, making them interchangeable with post-cure temperature and viscosity flow adjustments.
Side-by-Side ASTM Mechanical, Thermal, Rheological & Pricing Delta
| ASTM Parameter | A: HK Research MaxGuard NP White Marine ISO/NPG Gelcoat (HK Research Corp) | B: Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester (Interplastic Corp) | Engineering Delta (A vs. B) |
|---|---|---|---|
| OEM Manufacturer & SKU | HK Research Corp • HKR-MGNP-55DR | Interplastic Corp • IPC-SIL95BA | Cross-Brand OEM Equivalent |
| ASTM D638 Tensile Strength (MPa / PSI) | 72 MPa (10,443 psi) | 66 MPa (9,573 psi) | +6 MPa (+9.1 %) |
| ASTM D648 Heat Deflection Temp (HDT °C / °F) | 88 °C (190 °F) | 75 °C (167 °F) | +13 °C (Verify Post-Cure) |
| ASTM D790 Flexural Strength (MPa) | 128 MPa | 114 MPa | +14 MPa (+12.3 %) |
| ASTM D2583 Barcol Hardness | 45 | 40 | +5 Barcol |
| ASTM D2196 Brookfield Viscosity @ 25°C | 14500 cPs | 460 cPs | +14040 cPs (+3052.2 %) |
| Gel Time @ 25°C (Minutes) | 14 min | 24 min | -10 min |
| ASTM D792 Specific Density (kg/m³) | 1260 kg/m³ | 1115 kg/m³ | +145 kg/m³ |
| US DOT 49 CFR & TDG Hazmat Class | Class 3 Flammable Liquid (UN1866) | Class 3 Flammable Liquid (UN1866) | Identical (UN1866) |
| Unit Price ($/kg USD) & Pack Price | $8.6/kg • $1,950 (227 kg (55 Gal Drum)) | $7.8/kg • $1,755 (225 kg Steel Drum) | +0.8 $/kg (+10.3 %) |
| US Stocking Warehouses | Hickory, NC • St. Petersburg, FL • Fort Lauderdale, FL | Lakeland, FL • Houston, TX • Minneapolis, MN | 1–3 Days LTL Dispatch |
Both matrices cross-link via free-radical polymerization using 1.25%–2.0% MEKP (Methyl Ethyl Ketone Peroxide, UN3105) or Cumene Hydroperoxide (CHP) with Cobalt Octoate promoter. Low-hydrogen-peroxide MEKP (e.g., Norox MEKP-925H) is recommended to eliminate micro-foaming.
Post-Cure Schedule Adjustment Advised: ASTM D648 HDT differs by 13 °C (88 °C vs. 75 °C). For elevated-temperature tooling or dark-colored marine hulls, perform a 4–6 hour post-cure ramp at 60–80 °C (140–176 °F) to lock in full cross-link density.
Identical Hazmat Logistics Profile: Both SKUs ship under US DOT 49 CFR & Transport Canada TDG as Class 3 Flammable Liquid (UN Number: UN1866). Note 49 CFR § 177.848 segregation if ordering with Class 5.2 Organic Peroxides (UN3105).
Engineering FAQ: HK Research MaxGuard NP White Marine ISO/NPG Gelcoat vs. Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester
1. Is HK Research MaxGuard NP White Marine ISO/NPG Gelcoat a direct drop-in equivalent for Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester?▼
HK Research MaxGuard NP White Marine ISO/NPG Gelcoat (HK Research Corp) and Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester (Interplastic Corp) achieve a 68% ASTM engineering compatibility score in Marine ISO/NPG Gelcoats, Structural Bonding Pastes & Mold Releases. Tensile strength delta is +6 MPa (+9.1%) and thermal HDT delta is +13 °C, making them interchangeable with post-cure temperature and viscosity flow adjustments.
2. What is the ASTM D638 Tensile Strength and ASTM D648 HDT difference between HK Research MaxGuard NP White Marine ISO/NPG Gelcoat and Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester?▼
HK Research MaxGuard NP White Marine ISO/NPG Gelcoat (HK Research Corp) delivers ASTM D638 Tensile Strength of 72 MPa (10,443 psi) and ASTM D648 HDT of 88 °C, whereas Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester (Interplastic Corp) delivers 66 MPa (9,573 psi) and HDT of 75 °C. The net delta is +6 MPa (+9.1 %) tensile and +13 °C HDT.
3. Do HK Research MaxGuard NP White Marine ISO/NPG Gelcoat and Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester use the same catalyst or hardener cure system?▼
Both matrices cross-link via free-radical polymerization using 1.25%–2.0% MEKP (Methyl Ethyl Ketone Peroxide, UN3105) or Cumene Hydroperoxide (CHP) with Cobalt Octoate promoter. Low-hydrogen-peroxide MEKP (e.g., Norox MEKP-925H) is recommended to eliminate micro-foaming. Post-Cure Schedule Adjustment Advised: ASTM D648 HDT differs by 13 °C (88 °C vs. 75 °C). For elevated-temperature tooling or dark-colored marine hulls, perform a 4–6 hour post-cure ramp at 60–80 °C (140–176 °F) to lock in full cross-link density.
4. How do US DOT 49 CFR Hazmat shipping rules and B2B drum/pack prices compare between HK Research MaxGuard NP White Marine ISO/NPG Gelcoat and Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester?▼
Identical Hazmat Logistics Profile: Both SKUs ship under US DOT 49 CFR & Transport Canada TDG as Class 3 Flammable Liquid (UN Number: UN1866). Note 49 CFR § 177.848 segregation if ordering with Class 5.2 Organic Peroxides (UN3105). In US B2B distribution, HK Research MaxGuard NP White Marine ISO/NPG Gelcoat is priced at $1,950 per 227 kg (55 Gal Drum) ($8.6/kg) vs. $1,755 per 225 kg Steel Drum ($7.8/kg) for Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester (delta: +0.8 USD/kg).
Related Drop-In Comparisons in Marine ISO/NPG Gelcoats, Structural Bonding Pastes & Mold Releases
HK Research MaxGuard NP White Marine ISO/NPG Gelcoat (HK Research Corp) and Interplastic Silmar SIL95BA-41 Crystal Clear Surfboard Polyester (Interplastic Corp) are trademarks of their respective owners. CompositeMatrix Technologies Inc. is an independent North American B2B composite material intelligence registry; comparative ASTM D638, D648, D790, D2583, and D2196 figures are presented under the US legal doctrine of Nominative Fair Use (Lanham Act, 15 U.S.C. § 1125) and Feist Publications, Inc. v. Rural Telephone Service Co. (499 U.S. 340) for scientific and industrial cross-reference. Cure schedules, exotherm behavior, and laminate qualification must be verified by a licensed Naval Architect or Professional Engineer (PE) against current manufacturer batch Technical Data Sheets (TDS) and Safety Data Sheets (SDS).