DAIP
ASTM D5948 Type SDI, D5948 Type GDI-30 · also MIL-M-14 Type GDI
DAIP is the diallyl isophthalate version of the allyl thermoset family, listed as ASTM D5948 Type SDI and GDI-30 and as MIL-M-14 Type GDI, and supplied as filled moulding compound.
Reference datasheet — DAIP is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the GDI-30 condition
DAIP grades and fills
DAIP is supplied in 5 conditions, soft to hard. GDI-30 is the default FabDigit quotes; the values on this page are for it.
Compare all 5 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Short synthetic-fiber / low-filler DAIP, fine-detail molding | Select the low-filler, short synthetic-fiber grade for thin-wall fine-detail insulators and multi-cavity precision transfer molding, where flow matters more than the 38 MPa strength. | 38 | 1.4 | 100 HRM | |
Mineral/silica filled DAIP compound | Choose the mineral/silica-filled compound for low-cost encapsulation and switch insulation needing low CTE and arc resistance; impact strength is the lowest of the family. | 38 | 0.4 | 112 HRM | |
Synthetic (acrylic/polyester) fiber filled DAIP | Use the synthetic-fiber filled grade for thin-wall insulators and high-frequency or high-voltage tracking duty: 1.58 g/cm³ density, low dielectric loss and good precision machining at 42 MPa. | 42 | 0.9 | ||
Flame-retardant 30% glass-filled DAIP | Choose the flame-retardant 30% glass-filled version when thin-wall V-0, low smoke or strict fire certification governs; strength drops to 50 MPa and service temperature to 200 °C. | 50 | 0.5 | 105 HRM | |
GDI-30Default 30% glass-fiber reinforced DAIP molding compound | Pick the 30% glass-fiber molding compound for military and aerospace connector insulators: highest stiffness, heat-deflection and 205 °C service for pin-loaded structures, at the cost of machinability. | 55 | 0.6 |
Supply forms, finishes and certifications
Ways DAIP is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
RESIN | Unfilled DAIP prepolymer / monomer resin | Supply form |
What is DAIP?
DAIP is the diallyl isophthalate version of the allyl thermoset family, listed as ASTM D5948 Type SDI and GDI-30 and as MIL-M-14 Type GDI, and supplied as filled moulding compound. It offers the same dimensional stability and low moisture absorption as DAP with higher thermal stability — 1.8 g/cm³ density, 55 MPa tensile strength, 0.6 % elongation and service to 205 °C — which is why it is used for military and aerospace connectors. It is brittle, abrasive to tooling (machinability 40), and thick sections need post-cure; where 180 °C service is enough, DAP is the lower-cost choice. DAIP has a density of 1.8 g/cm³ (0.065 lb/in³), heavier than 95% of polymer grades. Its glass-transition temperature is 190°C (374 °F). DAIP has a tensile strength of 55 MPa (7.98 ksi), stronger than 61% of polymer grades. Elongation at break is 0.6% and the elastic modulus is 11 GPa (1.6 Msi).
What is DAIP used for?
- Mil-spec connectors
- High-reliability electrical housings
- Aerospace terminal blocks
Advantages
- Stiff — 11 GPa (1.6 Msi), better than 97% of polymer grades
- Conducts heat well — 0.42 W/m·K (0.243 BTU/hr·ft·°F), better than 95% of polymer grades
- High service temperature — 205°C (401 °F), better than 88% of polymer grades
- Low, predictable mold shrinkage — 0.35%, better than 86% of polymer grades
- Good UV / weathering resistance — 70/100, better than 83% of polymer grades
Limitations
- Limited ductility — 0.6%, worse than 99% of polymer grades
- Limited formability — 3/100, worse than 99% of polymer grades
- Heavy — 1.8 g/cm³ (0.065 lb/in³), worse than 95% of polymer grades
- Difficult to weld — 3/100, worse than 95% of polymer grades
- Difficult to machine — 40/100, worse than 82% of polymer grades
DAIP properties
Typical room-temperature values for DAIP-GDI-30; bars are the position among polymer grades.
Physical4
DAIP has a density of 1.8 g/cm³ (0.065 lb/in³), heavier than 95% of polymer grades. Its glass-transition temperature is 190°C (374 °F).
Mechanical9
DAIP has a tensile strength of 55 MPa (7.98 ksi), stronger than 61% of polymer grades. Elongation at break is 0.6% and the elastic modulus is 11 GPa (1.6 Msi).
Thermal10
DAIP is rated for continuous service to 205°C (401 °F). It conducts heat at 0.42 W/m·K (0.243 BTU/hr·ft·°F), better than 95% of polymer grades. Thermal expansion is 30 µm/m·K (16.7 µin/in·°F).
Electrical7
DAIP is an electrical insulator with a dielectric strength of 16 kV/mm (406.4 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), better than 65% of polymer grades. UV resistance is very good.
Sustainability4
Producing a kilogram of DAIP takes about 105 MJ of energy and emits 5.5 kg of CO₂ — more than 54% of polymer grades. Typical recycled content is 0%.
Manufacturability7
DAIP's machinability is fair (40/100, worse than 82% of polymer grades); weldability not recommended (3/100); formability not recommended (3/100).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. DAIP is highlighted; hover a dot for its name, or open the interactive family chart.
Working with DAIP
Is DAIP easy to machine?
Cured parts can be turned, milled and drilled, but they are brittle and abrasive: use diamond or carbide tooling at high speed and low feed, and place a backing plate on the exit side to prevent chipping. Extract glass dust at source.
Can DAIP be welded?
Thermoset — no melt welding is possible. Use epoxy or cyanoacrylate bonding, or mechanical fastening.
Can DAIP be formed, bent or molded?
Mainly compression and transfer moulding, with thermoset screw injection also possible: material temperature 85–120 °C, mould temperature 150–180 °C, cure 45–180 s. Thick-walled parts need tool venting and a post-cure at 150–200 °C for several hours to stabilise dimensions and electrical properties.
DAIP chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| diallyl isophthalate prepolymer + monomediallyl isophthalate prepolymer/monomer matrix | 25 – 45 | 35 |
| glass fiberchopped glass fiber (GDI-30) | 25 – 35 | 30 |
| organic peroxide initiator (e.g. dicumylcure initiator | 0.3 – 2 | 1 |
| mold release / lubricant (metal stearate | 0.3 – 1.5 | 0.8 |
| pigment / colorantblue/black identification colors common in military parts | 0 – 2 | 1 |
| mineral filler (silica / clay / CaCO3)balance of filler; sets CTE and electrical properties | ≥ 20 (balance) |
What surface finishes work on DAIP?
Deflash with cryogenic dry ice or media blasting. The surface can be painted or selectively metallised; plasma or chemical roughening is required before plating deep holes. Mirror polishing is neither needed nor practical.
Equivalent designations
Standards and trade names that resolve to DAIP in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- D5948 Type SDID5948 Type GDI-30
- Trade names
- MIL-M-14 Type GDI
How much does DAIP cost?
DAIP is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
DAIP — frequently asked
What is DAIP used for?
DAIP is typically used for mil-spec connectors, high-reliability electrical housings and aerospace terminal blocks. In short: 205 °C allyl thermoset; mil-spec connector material; higher-temperature DAP alternative.
What is the tensile strength of DAIP?
DAIP has a typical tensile strength of 55 MPa (7.98 ksi) — stronger than 61% of polymer grades. Strength varies by condition: see the 5 listed tempers.
Is DAIP easy to machine?
Not especially — machinability is rated fair (40/100, worse than 82% of polymer grades). Cured parts can be turned, milled and drilled, but they are brittle and abrasive: use diamond or carbide tooling at high speed and low feed, and place a backing plate on the exit side to prevent chipping. Extract glass dust at source.
Can DAIP be welded?
Not readily — weldability is rated not recommended (3/100). Thermoset — no melt welding is possible. Use epoxy or cyanoacrylate bonding, or mechanical fastening.
What surface finishes work on DAIP?
Deflash with cryogenic dry ice or media blasting. The surface can be painted or selectively metallised; plasma or chemical roughening is required before plating deep holes. Mirror polishing is neither needed nor practical.
Can DAIP be formed, bent or molded?
Mainly compression and transfer moulding, with thermoset screw injection also possible: material temperature 85–120 °C, mould temperature 150–180 °C, cure 45–180 s. Thick-walled parts need tool venting and a post-cure at 150–200 °C for several hours to stabilise dimensions and electrical properties.
What is the maximum service temperature of DAIP?
DAIP is rated for continuous use to about 205°C (401 °F), and briefly to 260°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does DAIP cost?
DAIP is a high-cost polymer ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM D5948 — Standard Specification for Molding Compounds, Thermosetting — ASTM International (2019)
- MIL-M-14H — Molding Plastics and Molded Plastic Parts, Thermosetting — US DoD (1989)
- ASTM D638 / D790 / D256 / D648 / D150 / D257 / D570 test methods — ASTM International (2022)
- Engineered Materials Handbook Vol.2 — Engineering Plastics (allyl resins) — ASM International (1988)
- DAISO ISODAP / DAP resin technical data — Osaka Soda (2022)
- Diallyl phthalate & diallyl isophthalate molding compound datasheets — Cosmic Plastics / Glenro / DAP (2023)
- DAP/DAIP (2025)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.