If the part must be a clear viewing window, begin with a specified solid PC grade. If it is an opaque welded vessel or chemical-process component, ask whether a named PP grade fits the fluids and joining method. Weight alone does not settle the choice. SinoPlastix supplies PC sheet and fabricated PC parts; PP is a comparison material, not a product offered here.
Send a drawing for a PC option Build a material brief
Decide from the function of the finished part
Swipe sideways to see all columns →
| Buyer requirement | PC question | PP question | Approval step |
|---|---|---|---|
| See through the panel | Which clear PC grade and thickness meet the transmission, haze and surface-finish target? | Does the proposed PP grade provide the required visibility? A grey PP-H tank sheet does not replace a clear window. | Inspect samples at final thickness, lighting and cleaning condition. |
| Contain or resist impact | What hazard, mounted opening, support and named test must the PC assembly meet? | Does the specific PP design meet that same requirement, including joints? | Compare assembly evidence, not a generic material toughness claim. |
| Contact chemicals | Test the offered PC grade at the actual concentration, temperature, stress and contact time. | Check the offered PP grade and weld or liner against the same process fluid. | Obtain fluid list, cleaning cycle and grade-specific compatibility evidence. |
| Join panels | Specify the PC adhesive, fastener or frame, edge detail and stress-control method. | A welded PP vessel needs a weldable grade, qualified weld detail and inspection plan. | Approve finished joint samples and the design load. |
| Temperature and creep | Request heat-deflection/use data under the actual load and duration for the offered PC grade. | Check the PP grade’s service condition, creep and support at the same load/duration. | Use comparable test methods and evaluate the whole part. |
A weight example that does not decide the material
The SinoPlastix representative solid PC density is 1.20 g/cm³ by ISO 1183-1. The SIMONA PP-H AlphaPlus sheet data sheet lists 0.91 g/cm³ by DIN EN ISO 1183. At nominal 6 mm, the densities calculate to 7.20 kg/m² for solid PC versus 5.46 kg/m² for this PP-H reference before frame, welds or hardware. The theoretical PP-H value is about 24% lower in this material-only example.
6 mm named PP-H reference · 5.46 kg/m²
The PP-H maker says its typical property table is generally based on approximate average values from 4 mm extruded sheet. We use that typical density to calculate a nominal 6 mm mass; 5.46 kg/m² is not a measured 6 mm production-sheet weight. The reference is a specific industrial tank/equipment grade, not every PP grade or a SinoPlastix product. Lower mass does not create optical clarity, chemical compatibility or equivalent impact protection. Confirm actual thickness, tolerances and grade with the PP supplier.
Three practical buying routes
- Clear guard or equipment window: start with solid PC and the guard-design questions. Send the hazard, opening, frame and required test.
- Opaque welded process vessel: a PP supplier may be the right first call. Obtain its exact grade, weld procedure, fluid compatibility and service conditions; SinoPlastix does not quote PP sheet.
- Unsure whether PP or PC is necessary: state the visibility, fluids, cleaning, impact consequence, size and drawings. We can quote a PC option if it meets the brief and identify the criteria that need testing.
Send the information that changes the PC quotation
Provide the part drawing and revision, sheet dimensions/quantity, target visibility and surface finish, operating temperature, load and impact hazard, chemicals with concentration and contact time, joining/support detail, destination and named test or report requirement. Common original test reports can be requested from sales. The written custom quote confirms specification, actual price and lead time; website averages are planning references.
Request a PC alternative Ask about test documents
Questions buyers ask
Is PP always lighter than solid PC?
The named 6 mm example calculates to 5.46 kg/m² for PP-H versus 7.20 kg/m² for representative solid PC. Confirm the offered grades, thickness and tolerances. Lower material mass does not make PP suitable for a clear viewing panel or an impact-rated assembly.
Which material is better for chemical contact?
There is no useful universal answer without the chemical, concentration, temperature, stress, contact duration and joint design. Check compatibility evidence for the exact PC or PP grade and finished part.
Can SinoPlastix supply PP sheets?
PP is compared here as an alternative material. SinoPlastix quotes custom polycarbonate sheet and fabricated PC parts. Share your application and PP specification if you want us to evaluate a PC option.