C5/C9 Copolymer Hydrocarbon Resin offers a grade-dependent, ratio-tunable glass transition temperature (Tg) positioned between the C5 aliphatic window (44–58 degrees C) and the C9 aromatic window (approximately 80 degrees C), with the exact value set by the C5:C9 ratio and polymerization conditions [1][2]. This makes it suitable for some low-temperature applications, but performance depends on grade, molecular weight, and whether the resin is hydrogenated [1][3]. The resin functions as a tackifier, not a standalone structural material, and should be validated in the specific formulation [3][4].
1. What Is C5/C9 Copolymer Hydrocarbon Resin?
C5/C9 copolymer hydrocarbon resin is a thermoplastic resin produced by copolymerizing C5 fractions (aliphatic olefins) and C9 fractions (aromatic compounds) from petroleum cracking [1][4]. It sits between pure C5 Hydrocarbon Resin (fully aliphatic) and pure C9 aromatic resin in both polarity and Tg [1][3]. It is used as a tackifier in adhesives, rubber compounds, and sealants [3][4]. A dedicated C5/C9 Copolymer Hydrocarbon Resin grade is specified for Tg, softening point, and molecular weight depending on the application.
2. Glass Transition Temperature (Tg): What the Data Show
Tg is the temperature at which a resin transitions from a rubbery state to a glassy, brittle state. It is a critical parameter for low-temperature performance [1][3].
| Resin Type | Typical Tg Range | Method / Source | Reference |
|---|---|---|---|
| C5 aliphatic (representative) | 40–60 degrees C (PICCOTAC 1100 Tg 46 degrees C; PICCOTAC 1115 Tg 58 degrees C) | DSC | [5][6] |
| C9 aromatic (representative) | approximately 80 degrees C (literature-classified reference value) | DSC / supplier data | [11] |
| C5/C9 copolymer (tunable) | ratio-dependent; grade-specific values from supplier TDS | DSC | [1][2] |
| Hydrogenated C9 | 40–70 degrees C (REGALREZ 1094 Tg 40 degrees C; REGALREZ 1126 Tg 65 degrees C) | DSC | [7][8][10] |
Important: Tg values are highly grade-dependent. A "C5 resin" or "C9 resin" is not a single specification. Always confirm Tg with the supplier TDS for the exact grade [1][2][5][6].
3. Molecular Weight and Its Effect on Low-Temperature Performance
Molecular weight affects both Tg and cohesion [1][3]. C5/C9 copolymer resin molecular weights are grade-dependent; a representative fully hydrogenated tackifier shows Mn 550 g/mol and Mw 928 g/mol by GPC [7], and copolymer grades span wider ranges documented by supplier TDS [2]. Lower molecular weight generally lowers Tg and increases flexibility but reduces cohesion; higher molecular weight increases cohesion but may raise Tg and reduce low-temperature flexibility. The optimum depends on the balance required for the specific application [1][3].
4. What This Article Does NOT Claim
- No universal Tg for "C5/C9 copolymer." Tg is ratio-dependent; no universal value applies. Representative copolymer Tg values must be confirmed from supplier TDS for the exact grade [1][2].
- No claim that C5 resin has a Tg of −20 degrees C to −10 degrees C. Representative C5 aliphatic resins show Tg in the 40–60 degrees C range (PICCOTAC 1100 Tg 46 degrees C; PICCOTAC 1115 Tg 58 degrees C) [5][6].
- No claim that hydrogenated C9 resin has a Tg of 5 degrees C. Typical values are 40–70 degrees C (REGALREZ 1094 Tg 40 degrees C; REGALREZ 1126 Tg 65 degrees C) [7][8].
- No specific customer case data or percentage performance improvements. Application-specific testing is required.
5. Quality Parameters to Request Before Evaluation
| Parameter | Typical Method | What It Tells You |
|---|---|---|
| Tg | DSC (ASTM D6604 practice) | Low-temperature flexibility window [1][2][5][6] |
| Mn and Mw | GPC | Cohesion and viscosity [2][7] |
| Softening point | ASTM E28 | Processing temperature [9][12] |
| C5:C9 ratio | Supplier TDS (e.g., H-NMR) | Balance of aliphatic and aromatic character [1][2] |
| Hydrogenation degree (if applicable) | Supplier TDS | Color and stability [7][8][10] |
| Batch-specific COA | Supplier COA | Confirms delivered batch values |
6. Conclusion
As the preceding sections show, the low-temperature performance of C5/C9 copolymer hydrocarbon resin is governed primarily by Tg, which is ratio-dependent and grade-specific: C5 aliphatic resins anchor at Tg 46–58 degrees C (PICCOTAC 1100/1115) [5][6]; C9 aromatic resins anchor around 80 degrees C [11]; fully hydrogenated C9 grades anchor at 40–65 degrees C (REGALREZ 1094/1126) [7][8]; and C5/C9 copolymer grades fall between these windows depending on C5:C9 ratio [1][2]. Molecular weight affects both Tg and cohesion, with a representative hydrogenated grade showing Mn 550/Mw 928 by GPC [7]. No universal Tg value applies to "C5/C9 copolymer"; every value must be confirmed against supplier TDS, batch COA, and application-specific trial on the actual formulation.
7. Next Step
If you are evaluating C5/C9 Copolymer Hydrocarbon Resin for a low-temperature application, send us:
- Target Tg range
- Base polymer type (NR, SIS, EVA, etc.)
- Application (PSA, rubber compound, sealant)
- Service temperature range
- Molecular weight requirement (Mn/Mw)
- Required documentation (TDS, COA, DSC data)
We will recommend a suitable grade and provide batch-specific Tg and molecular weight data for your evaluation.
Request C5/C9 Copolymer TDS and Tg Data →
References
- Mildenberg, R.; Zander, M.; Collin, G. Hydrocarbon Resins. VCH, Weinheim, 1997. ISBN 3-527-28617-9. [Documents C5/C9 resin composition and structure–property relationships.]
- Tosoh. Petrotack® C5/C9 Copolymer Petroleum Resin: Product Data. [Grades Petrotack 60/70/90/90V/100V; C5 content 30–70% by H-NMR; R&B softening point 72–96 degrees C; Gardner color 6–7; bromine number 35–50; acid value 0.1 max.]
- Satas, D. (Ed.). Handbook of Pressure Sensitive Adhesive Technology, 3rd ed. Satas & Associates, Stamford, CT, 1999. [Documents tackifier function and low-temperature performance principles.]
- Lesco Chemical. Petroleum Resin Introduction. [C5 (aliphatic), C9 (aromatic), DCPD, and copolymer resins; used as tackifiers.]
- Synthomer. PICCOTAC™ 1100 Hydrocarbon Resin TDS. [Aliphatic C5 resin; Tg 46 degrees C (DSC midpoint); softening point 101 degrees C.]
- Synthomer. PICCOTAC™ 1115 Hydrocarbon Resin TDS. [Aliphatic C5 resin; Tg 58 degrees C (DSC midpoint); softening point 112 degrees C.]
- Synthomer. REGALREZ™ 1094 Hydrocarbon Resin TDS. [Fully hydrogenated; R&B 95 degrees C; Tg 40 degrees C (DSC midpoint); Mn 550; Mw 928; polydispersity 1.71.]
- Synthomer. REGALREZ™ 1126 Hydrocarbon Resin TDS. [Tg 65 degrees C (DSC midpoint).]
- Arakawa Chemical. Arkon™ P Series Hydrogenated Hydrocarbon Resin Product Data. [P-90/P-100/P-115/P-125/P-140; R&B 90–140 degrees C; for PSA and hot melt adhesive applications.]
- Orke Chemical. C9 Hydrogenated Petroleum Resin: Product Overview. [Supplier background. Typical Tg 40–70 degrees C by DSC.]
- Supplier-documented C9 aromatic resin reference value. [Tg approximately 80 degrees C by DSC; literature-classified C9 resin properties.]
- ASTM International. ASTM D6604: Standard Practice for Glass Transition Temperatures by DSC of Hydrocarbon Resins; and ASTM E28: Softening Point by Ring-and-Ball Apparatus. West Conshohocken, PA: ASTM. [Standard methods referenced by Tg and softening point data in this article.]
